Re: Electrical and General knowledge
On Thu, 4 Jan 2001, Tony van Ree wrote: > > A couple of thoughts based on the PVC fault thread but looking at a different angle. > > Should we as aspiring "communications experts" understand: > 1 Fundamental electrical and magnetic propogation theory. > 2 Basic cabling technology, design and termination. Just depends on how valuable you want to be... andy _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Electrical and General knowledge
At 10:01 AM 1/4/01, Tony van Ree wrote: >A couple of thoughts based on the PVC fault thread but looking at a >different angle. > >Should we as aspiring "communications experts" understand: >1 Fundamental electrical and magnetic propogation theory. >2 Basic cabling technology, design and termination. Yes. Cisco Networking Academy requires almost a whole semester on electricity, cabling, building wiring, etc. Now, I think that's overkill, but at least some study in these areas is a good idea if you want to be an efficient troubleshooter. Priscilla >Well lets consider the number of faults that can be put into this >category. It used to be 75%+ faults were of a physical nature. I think >the figure would still be quite high but I don't have recent figures. > >Most intermittent faults are due to connections and/or connectors. Ofter >due to poor installation and/or plugs being inserted and removed regularly >and/or incorrectly. > >The next most common cause of intermittent faults is magnetic (Noise) >interferance. Usually due to poor cabling layouts and/or poor >installation methods. > >The most common cause of permanent damage to to ports is due to incorrect >installation of cables (NT1 to Ethernet ports is a good one that comes up >a lot). > >In switching the most common problems are duplex mismatches. Usually due >to a misunderstanding of what duplex setting do. > >These are just some considerations there are heaps more. Most are easily >avoided but difficult to diagnose. An understanding of the fundamentals >involved can avoid disaster. > >Just as a beat up on all. I work in an environment where we supply Telco >type services and IP connectivity to thousands (this figure is an >understatement). A part of my job is to troubleshoot client connections >to our access servers. I can often go for a week or two handling about 10 >faults or more per day without finding a fault in the configuration of the >access servers, connections to the access servers and/or the clients >CPE. This does not leave much but I'll bet most still blame us. I don't >know how often I will suggest change this setting in your server an all >will be fine. Bink up it comes and so does the question "what did you do >at your end to fix my server?" > >Incidently the next most common problem I come across is username/password >errors particularly where people mix cases and/or use non alphanumeric >characters in usernames. In my opinoin this shouls be avoided (In Cisco's >also). The term username in the Cisco sense is really a hostname (PPP) >and should follow the Unix Hostmane rules to avoid stange issues. > >Most faults a simple and can be avoided by careful planning. > >Just some thoughts and ramblings from Teunis > >Teunis >Hobart, Tasmania >Australia > > >-- >www.tasmail.com > > >_ >FAQ, list archives, and subscription info: >http://www.groupstudy.com/list/cisco.html >Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Priscilla Oppenheimer http://www.priscilla.com _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Electrical and General knowledge
What about becoming BICSI certified? "Priscilla Oppenheimer" <[EMAIL PROTECTED]> wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > At 10:01 AM 1/4/01, Tony van Ree wrote: > > >A couple of thoughts based on the PVC fault thread but looking at a > >different angle. > > > >Should we as aspiring "communications experts" understand: > >1 Fundamental electrical and magnetic propogation theory. > >2 Basic cabling technology, design and termination. > > Yes. Cisco Networking Academy requires almost a whole semester on > electricity, cabling, building wiring, etc. Now, I think that's overkill, > but at least some study in these areas is a good idea if you want to be an > efficient troubleshooter. > > Priscilla > > >Well lets consider the number of faults that can be put into this > >category. It used to be 75%+ faults were of a physical nature. I think > >the figure would still be quite high but I don't have recent figures. > > > >Most intermittent faults are due to connections and/or connectors. Ofter > >due to poor installation and/or plugs being inserted and removed regularly > >and/or incorrectly. > > > >The next most common cause of intermittent faults is magnetic (Noise) > >interferance. Usually due to poor cabling layouts and/or poor > >installation methods. > > > >The most common cause of permanent damage to to ports is due to incorrect > >installation of cables (NT1 to Ethernet ports is a good one that comes up > >a lot). > > > >In switching the most common problems are duplex mismatches. Usually due > >to a misunderstanding of what duplex setting do. > > > >These are just some considerations there are heaps more. Most are easily > >avoided but difficult to diagnose. An understanding of the fundamentals > >involved can avoid disaster. > > > >Just as a beat up on all. I work in an environment where we supply Telco > >type services and IP connectivity to thousands (this figure is an > >understatement). A part of my job is to troubleshoot client connections > >to our access servers. I can often go for a week or two handling about 10 > >faults or more per day without finding a fault in the configuration of the > >access servers, connections to the access servers and/or the clients > >CPE. This does not leave much but I'll bet most still blame us. I don't > >know how often I will suggest change this setting in your server an all > >will be fine. Bink up it comes and so does the question "what did you do > >at your end to fix my server?" > > > >Incidently the next most common problem I come across is username/password > >errors particularly where people mix cases and/or use non alphanumeric > >characters in usernames. In my opinoin this shouls be avoided (In Cisco's > >also). The term username in the Cisco sense is really a hostname (PPP) > >and should follow the Unix Hostmane rules to avoid stange issues. > > > >Most faults a simple and can be avoided by careful planning. > > > >Just some thoughts and ramblings from Teunis > > > >Teunis > >Hobart, Tasmania > >Australia > > > > > >-- > >www.tasmail.com > > > > > >_ > >FAQ, list archives, and subscription info: > >http://www.groupstudy.com/list/cisco.html > >Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > > > > > Priscilla Oppenheimer > http://www.priscilla.com > > _ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Electrical and General knowledge
Sorry, if I understand your comments on passwords, I must disagree. Username passwords should contain non-alphabetic characters. This doesn't effect Cisco, because so far no one seems to have created the right software to hack the secret password hash. However, the Cisco secret password hash is similar to Microsoft's, and l0pht has long ago created a brute force hack. I ran the l0pht crack on my userlist 2 months ago. The only passwords that were NOT cracked were mine and my student worker's. Both had non-alphabetic characters. Ray Mosely CCNA, MCSE -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Priscilla Oppenheimer Sent: Wednesday, January 03, 2001 5:37 PM To: Tony van Ree; studygroup Subject: Re: Electrical and General knowledge At 10:01 AM 1/4/01, Tony van Ree wrote: >A couple of thoughts based on the PVC fault thread but looking at a >different angle. > >Should we as aspiring "communications experts" understand: >1 Fundamental electrical and magnetic propogation theory. >2 Basic cabling technology, design and termination. Yes. Cisco Networking Academy requires almost a whole semester on electricity, cabling, building wiring, etc. Now, I think that's overkill, but at least some study in these areas is a good idea if you want to be an efficient troubleshooter. Priscilla >Well lets consider the number of faults that can be put into this >category. It used to be 75%+ faults were of a physical nature. I think >the figure would still be quite high but I don't have recent figures. > >Most intermittent faults are due to connections and/or connectors. Ofter >due to poor installation and/or plugs being inserted and removed regularly >and/or incorrectly. > >The next most common cause of intermittent faults is magnetic (Noise) >interferance. Usually due to poor cabling layouts and/or poor >installation methods. > >The most common cause of permanent damage to to ports is due to incorrect >installation of cables (NT1 to Ethernet ports is a good one that comes up >a lot). > >In switching the most common problems are duplex mismatches. Usually due >to a misunderstanding of what duplex setting do. > >These are just some considerations there are heaps more. Most are easily >avoided but difficult to diagnose. An understanding of the fundamentals >involved can avoid disaster. > >Just as a beat up on all. I work in an environment where we supply Telco >type services and IP connectivity to thousands (this figure is an >understatement). A part of my job is to troubleshoot client connections >to our access servers. I can often go for a week or two handling about 10 >faults or more per day without finding a fault in the configuration of the >access servers, connections to the access servers and/or the clients >CPE. This does not leave much but I'll bet most still blame us. I don't >know how often I will suggest change this setting in your server an all >will be fine. Bink up it comes and so does the question "what did you do >at your end to fix my server?" > >Incidently the next most common problem I come across is username/password >errors particularly where people mix cases and/or use non alphanumeric >characters in usernames. In my opinoin this shouls be avoided (In Cisco's >also). The term username in the Cisco sense is really a hostname (PPP) >and should follow the Unix Hostmane rules to avoid stange issues. > >Most faults a simple and can be avoided by careful planning. > >Just some thoughts and ramblings from Teunis > >Teunis >Hobart, Tasmania >Australia > > >-- >www.tasmail.com > > >_ >FAQ, list archives, and subscription info: >http://www.groupstudy.com/list/cisco.html >Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Priscilla Oppenheimer http://www.priscilla.com _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Electrical and General knowledge
Ray, I think there is a misunderstanding. What he said was non alphanumeric (something other that letters and numbers). What I think he means is characters such as !@#$%^&*(), and others. Alphabetic characters, numbers, and especially mixed case are very much recommended for security, BUT, I can understand the problems associated with a user not remembering that he had the 3rd letter of his cat's name capitalized. My $ 0.02 Brad Brad Stanfield CCNA Network/Integration Engineer [EMAIL PROTECTED] Government Micro Resources Network Operations Control Center Norfolk Naval Shipyard Bldg 33 NAVSEA NCOE 757-393-9526 1-800-626-6622 -Original Message- From: Ray Mosely [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 04, 2001 9:14 AM To: studygroup Subject: RE: Electrical and General knowledge Sorry, if I understand your comments on passwords, I must disagree. Username passwords should contain non-alphabetic characters. This doesn't effect Cisco, because so far no one seems to have created the right software to hack the secret password hash. However, the Cisco secret password hash is similar to Microsoft's, and l0pht has long ago created a brute force hack. I ran the l0pht crack on my userlist 2 months ago. The only passwords that were NOT cracked were mine and my student worker's. Both had non-alphabetic characters. Ray Mosely CCNA, MCSE -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Priscilla Oppenheimer Sent: Wednesday, January 03, 2001 5:37 PM To: Tony van Ree; studygroup Subject: Re: Electrical and General knowledge At 10:01 AM 1/4/01, Tony van Ree wrote: >A couple of thoughts based on the PVC fault thread but looking at a >different angle. > >Should we as aspiring "communications experts" understand: >1 Fundamental electrical and magnetic propogation theory. >2 Basic cabling technology, design and termination. Yes. Cisco Networking Academy requires almost a whole semester on electricity, cabling, building wiring, etc. Now, I think that's overkill, but at least some study in these areas is a good idea if you want to be an efficient troubleshooter. Priscilla >Well lets consider the number of faults that can be put into this >category. It used to be 75%+ faults were of a physical nature. I think >the figure would still be quite high but I don't have recent figures. > >Most intermittent faults are due to connections and/or connectors. Ofter >due to poor installation and/or plugs being inserted and removed regularly >and/or incorrectly. > >The next most common cause of intermittent faults is magnetic (Noise) >interferance. Usually due to poor cabling layouts and/or poor >installation methods. > >The most common cause of permanent damage to to ports is due to incorrect >installation of cables (NT1 to Ethernet ports is a good one that comes up >a lot). > >In switching the most common problems are duplex mismatches. Usually due >to a misunderstanding of what duplex setting do. > >These are just some considerations there are heaps more. Most are easily >avoided but difficult to diagnose. An understanding of the fundamentals >involved can avoid disaster. > >Just as a beat up on all. I work in an environment where we supply Telco >type services and IP connectivity to thousands (this figure is an >understatement). A part of my job is to troubleshoot client connections >to our access servers. I can often go for a week or two handling about 10 >faults or more per day without finding a fault in the configuration of the >access servers, connections to the access servers and/or the clients >CPE. This does not leave much but I'll bet most still blame us. I don't >know how often I will suggest change this setting in your server an all >will be fine. Bink up it comes and so does the question "what did you do >at your end to fix my server?" > >Incidently the next most common problem I come across is username/password >errors particularly where people mix cases and/or use non alphanumeric >characters in usernames. In my opinoin this shouls be avoided (In Cisco's >also). The term username in the Cisco sense is really a hostname (PPP) >and should follow the Unix Hostmane rules to avoid stange issues. > >Most faults a simple and can be avoided by careful planning. > >Just some thoughts and ramblings from Teunis > >Teunis >Hobart, Tasmania >Australia > > >-- >www.tasmail.com > > >_ >FAQ, list archives, and subscription info: >http://www.groupstudy.com/list/cisco.html >Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _
RE: Electrical and General knowledge
Within the confines of my (admittedly limited) understanding of the original author's point, the username/password pairs referred to are the ones used in processes such as CHAP authentication, and therefore do not pertain to end-user access to either intermediate or end systems (thereby somewhat obviating the "3rd letter of his cat's name capitalized" concern). Please let me know if I misunderstood to an unacceptable extent. Thanks, "Stanfield Hilman B (Brad) CONT NSSG" <[EMAIL PROTECTED]> @groupstudy.com on 01/04/2001 09:43:02 AM Please respond to "Stanfield Hilman B (Brad) CONT NSSG" <[EMAIL PROTECTED]> Sent by: [EMAIL PROTECTED] To: "'Ray Mosely'" <[EMAIL PROTECTED]>, studygroup <[EMAIL PROTECTED]> cc:(bcc: Kevin Cullimore) Subject: RE: Electrical and General knowledge Ray, I think there is a misunderstanding. What he said was non alphanumeric (something other that letters and numbers). What I think he means is characters such as !@#$%^&*(), and others. Alphabetic characters, numbers, and especially mixed case are very much recommended for security, BUT, I can understand the problems associated with a user not remembering that he had the 3rd letter of his cat's name capitalized. My $ 0.02 Brad Brad Stanfield CCNA Network/Integration Engineer [EMAIL PROTECTED] Government Micro Resources Network Operations Control Center Norfolk Naval Shipyard Bldg 33 NAVSEA NCOE 757-393-9526 1-800-626-6622 -Original Message- From: Ray Mosely [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 04, 2001 9:14 AM To: studygroup Subject: RE: Electrical and General knowledge Sorry, if I understand your comments on passwords, I must disagree. Username passwords should contain non-alphabetic characters. This doesn't effect Cisco, because so far no one seems to have created the right software to hack the secret password hash. However, the Cisco secret password hash is similar to Microsoft's, and l0pht has long ago created a brute force hack. I ran the l0pht crack on my userlist 2 months ago. The only passwords that were NOT cracked were mine and my student worker's. Both had non-alphabetic characters. Ray Mosely CCNA, MCSE -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Priscilla Oppenheimer Sent: Wednesday, January 03, 2001 5:37 PM To: Tony van Ree; studygroup Subject: Re: Electrical and General knowledge At 10:01 AM 1/4/01, Tony van Ree wrote: >A couple of thoughts based on the PVC fault thread but looking at a >different angle. > >Should we as aspiring "communications experts" understand: >1 Fundamental electrical and magnetic propogation theory. >2 Basic cabling technology, design and termination. Yes. Cisco Networking Academy requires almost a whole semester on electricity, cabling, building wiring, etc. Now, I think that's overkill, but at least some study in these areas is a good idea if you want to be an efficient troubleshooter. Priscilla >Well lets consider the number of faults that can be put into this >category. It used to be 75%+ faults were of a physical nature. I think >the figure would still be quite high but I don't have recent figures. > >Most intermittent faults are due to connections and/or connectors. Ofter >due to poor installation and/or plugs being inserted and removed regularly >and/or incorrectly. > >The next most common cause of intermittent faults is magnetic (Noise) >interferance. Usually due to poor cabling layouts and/or poor >installation methods. > >The most common cause of permanent damage to to ports is due to incorrect >installation of cables (NT1 to Ethernet ports is a good one that comes up >a lot). > >In switching the most common problems are duplex mismatches. Usually due >to a misunderstanding of what duplex setting do. > >These are just some considerations there are heaps more. Most are easily >avoided but difficult to diagnose. An understanding of the fundamentals >involved can avoid disaster. > >Just as a beat up on all. I work in an environment where we supply Telco >type services and IP connectivity to thousands (this figure is an >understatement). A part of my job is to troubleshoot client connections >to our access servers. I can often go for a week or two handling about 10 >faults or more per day without finding a fault in the configuration of the >access servers, connections to the access servers and/or the clients >CPE. This does not leave much but I'll bet most still blame us. I don't >know how often I will suggest change this setting in your server an all >will be fine. Bink up it comes and so does the question "what did you do
RE: Electrical and General knowledge
Nope, no misunderstanding. l0pht takes about 2 or 3 days to crack alphanumeric passwords that are hashed. It could take a month of Sundays to hack special characters. I always use at least one special character in my passwords. And it is just a matter of time before someone programs a brute force hash cracker for router access. The hash algorithm, as I understand it, it very similar to what Microsoft uses, and l0pht cracks. Mixed case characters are sometimes called a skyline font, because they resemble a city's skyline. Skyline passwords are easily cracked, so I don't really see the point to them, unless a hacker is using "social engineering" to discover passwords. Social engineering is basically eavesdropping by maintaining a physical presence when someone is typing in a password. Maybe hang out with a cup of coffee, chat a little, and wait for the opportunity to observe a user typing in a password. Ray M. CCNA, MCSE -Original Message- From: Stanfield Hilman B (Brad) CONT NSSG [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 04, 2001 8:43 AM To: 'Ray Mosely'; studygroup Subject: RE: Electrical and General knowledge Ray, I think there is a misunderstanding. What he said was non alphanumeric (something other that letters and numbers). What I think he means is characters such as !@#$%^&*(), and others. Alphabetic characters, numbers, and especially mixed case are very much recommended for security, BUT, I can understand the problems associated with a user not remembering that he had the 3rd letter of his cat's name capitalized. My $ 0.02 Brad Brad Stanfield CCNA Network/Integration Engineer [EMAIL PROTECTED] Government Micro Resources Network Operations Control Center Norfolk Naval Shipyard Bldg 33 NAVSEA NCOE 757-393-9526 1-800-626-6622 -Original Message- From: Ray Mosely [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 04, 2001 9:14 AM To: studygroup Subject: RE: Electrical and General knowledge Sorry, if I understand your comments on passwords, I must disagree. Username passwords should contain non-alphabetic characters. This doesn't effect Cisco, because so far no one seems to have created the right software to hack the secret password hash. However, the Cisco secret password hash is similar to Microsoft's, and l0pht has long ago created a brute force hack. I ran the l0pht crack on my userlist 2 months ago. The only passwords that were NOT cracked were mine and my student worker's. Both had non-alphabetic characters. Ray Mosely CCNA, MCSE -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Priscilla Oppenheimer Sent: Wednesday, January 03, 2001 5:37 PM To: Tony van Ree; studygroup Subject: Re: Electrical and General knowledge At 10:01 AM 1/4/01, Tony van Ree wrote: >A couple of thoughts based on the PVC fault thread but looking at a >different angle. > >Should we as aspiring "communications experts" understand: >1 Fundamental electrical and magnetic propogation theory. >2 Basic cabling technology, design and termination. Yes. Cisco Networking Academy requires almost a whole semester on electricity, cabling, building wiring, etc. Now, I think that's overkill, but at least some study in these areas is a good idea if you want to be an efficient troubleshooter. Priscilla >Well lets consider the number of faults that can be put into this >category. It used to be 75%+ faults were of a physical nature. I think >the figure would still be quite high but I don't have recent figures. > >Most intermittent faults are due to connections and/or connectors. Ofter >due to poor installation and/or plugs being inserted and removed regularly >and/or incorrectly. > >The next most common cause of intermittent faults is magnetic (Noise) >interferance. Usually due to poor cabling layouts and/or poor >installation methods. > >The most common cause of permanent damage to to ports is due to incorrect >installation of cables (NT1 to Ethernet ports is a good one that comes up >a lot). > >In switching the most common problems are duplex mismatches. Usually due >to a misunderstanding of what duplex setting do. > >These are just some considerations there are heaps more. Most are easily >avoided but difficult to diagnose. An understanding of the fundamentals >involved can avoid disaster. > >Just as a beat up on all. I work in an environment where we supply Telco >type services and IP connectivity to thousands (this figure is an >understatement). A part of my job is to troubleshoot client connections >to our access servers. I can often go for a week or two handling about 10 >faults or more per day without finding a fault in the configuration of the >access servers, connect
RE: Electrical and General knowledge
I think he must have been referring to the PPP CHAP username/password parameters. Making these ugly will cause you grief and not provide much security. For end-user passwords that protect access to servers, databases, router configs, etc, non-alphabetic characters should be included. Priscilla At 08:14 AM 1/4/01, Ray Mosely wrote: >Sorry, if I understand your comments on passwords, >I must disagree. Username passwords should contain >non-alphabetic characters. This doesn't effect Cisco, >because so far no one seems to have created the right >software to hack the secret password hash. > >However, the Cisco secret password hash is similar to >Microsoft's, and l0pht has long ago created a brute >force hack. I ran the l0pht crack on my userlist 2 >months ago. > >The only passwords that were NOT cracked were mine and >my student worker's. Both had non-alphabetic characters. > >Ray Mosely >CCNA, MCSE > >-Original Message- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of >Priscilla Oppenheimer >Sent: Wednesday, January 03, 2001 5:37 PM >To: Tony van Ree; studygroup >Subject: Re: Electrical and General knowledge > > >At 10:01 AM 1/4/01, Tony van Ree wrote: > > >A couple of thoughts based on the PVC fault thread but looking at a > >different angle. > > > >Should we as aspiring "communications experts" understand: > >1 Fundamental electrical and magnetic propogation theory. > >2 Basic cabling technology, design and termination. > >Yes. Cisco Networking Academy requires almost a whole semester on >electricity, cabling, building wiring, etc. Now, I think that's overkill, >but at least some study in these areas is a good idea if you want to be an >efficient troubleshooter. > >Priscilla > > >Well lets consider the number of faults that can be put into this > >category. It used to be 75%+ faults were of a physical nature. I think > >the figure would still be quite high but I don't have recent figures. > > > >Most intermittent faults are due to connections and/or connectors. Ofter > >due to poor installation and/or plugs being inserted and removed regularly > >and/or incorrectly. > > > >The next most common cause of intermittent faults is magnetic (Noise) > >interferance. Usually due to poor cabling layouts and/or poor > >installation methods. > > > >The most common cause of permanent damage to to ports is due to incorrect > >installation of cables (NT1 to Ethernet ports is a good one that comes up > >a lot). > > > >In switching the most common problems are duplex mismatches. Usually due > >to a misunderstanding of what duplex setting do. > > > >These are just some considerations there are heaps more. Most are easily > >avoided but difficult to diagnose. An understanding of the fundamentals > >involved can avoid disaster. > > > >Just as a beat up on all. I work in an environment where we supply Telco > >type services and IP connectivity to thousands (this figure is an > >understatement). A part of my job is to troubleshoot client connections > >to our access servers. I can often go for a week or two handling about 10 > >faults or more per day without finding a fault in the configuration of the > >access servers, connections to the access servers and/or the clients > >CPE. This does not leave much but I'll bet most still blame us. I don't > >know how often I will suggest change this setting in your server an all > >will be fine. Bink up it comes and so does the question "what did you do > >at your end to fix my server?" > > > >Incidently the next most common problem I come across is username/password > >errors particularly where people mix cases and/or use non alphanumeric > >characters in usernames. In my opinoin this shouls be avoided (In Cisco's > >also). The term username in the Cisco sense is really a hostname (PPP) > >and should follow the Unix Hostmane rules to avoid stange issues. > > > >Most faults a simple and can be avoided by careful planning. > > > >Just some thoughts and ramblings from Teunis > > > >Teunis > >Hobart, Tasmania > >Australia > > > > > >-- > >www.tasmail.com > > > > > >_ > >FAQ, list archives, and subscription info: > >http://www.groupstudy.com/list/cisco.html > >Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > > > > >Priscilla Oppenheimer >http://www.priscilla.com > >_
RE: Electrical and General knowledge
Hi, Sorry if I said it wrong. Passwords make what you like (as long as it is valid). Usernames however should be Alphanumeric and I think you will find with the 1st character Alpha is the recommended. Using non Alphanumeric characters in Usernames can cause wierd errors. Microsofts use of Underscores for example causes some DNS servers to gernerate huge numbers of error messages creating unnecessary issues. The use of upper and lower cases (Upper Microsoft preferred lower Unix) can cause all sorts of issues. For example a username Gof0rIt at the username statement becomes gof0rit at the dialer map easy done. The remote end will login and authenticate just fine. No data however will be forwarded. (BAD CONFIGS) Conversion of an NT server to Linux server. Uppercase password in NT usually finishes up lower case somewhere in the Linux. Authentication ok. No data transfer takes place. I see this a lot. That's why I put the comment there. Spending time on little things that can be avoided is most of my day. Teunis, Hobart, Tasmania Australia An open mind is the number one requirement in becoming a good trouble-shooter and I won't have it any other way. On Thursday, January 04, 2001 at 08:14:04 AM, Ray Mosely wrote: > Sorry, if I understand your comments on passwords, > I must disagree. Username passwords should contain > non-alphabetic characters. This doesn't effect Cisco, > because so far no one seems to have created the right > software to hack the secret password hash. > > However, the Cisco secret password hash is similar to > Microsoft's, and l0pht has long ago created a brute > force hack. I ran the l0pht crack on my userlist 2 > months ago. > > The only passwords that were NOT cracked were mine and > my student worker's. Both had non-alphabetic characters. > > Ray Mosely > CCNA, MCSE > > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of > Priscilla Oppenheimer > Sent: Wednesday, January 03, 2001 5:37 PM > To: Tony van Ree; studygroup > Subject: Re: Electrical and General knowledge > > > At 10:01 AM 1/4/01, Tony van Ree wrote: > > >A couple of thoughts based on the PVC fault thread but looking at a > >different angle. > > > >Should we as aspiring "communications experts" understand: > >1 Fundamental electrical and magnetic propogation theory. > >2 Basic cabling technology, design and termination. > > Yes. Cisco Networking Academy requires almost a whole semester on > electricity, cabling, building wiring, etc. Now, I think that's overkill, > but at least some study in these areas is a good idea if you want to be an > efficient troubleshooter. > > Priscilla > > >Well lets consider the number of faults that can be put into this > >category. It used to be 75%+ faults were of a physical nature. I think > >the figure would still be quite high but I don't have recent figures. > > > >Most intermittent faults are due to connections and/or connectors. Ofter > >due to poor installation and/or plugs being inserted and removed regularly > >and/or incorrectly. > > > >The next most common cause of intermittent faults is magnetic (Noise) > >interferance. Usually due to poor cabling layouts and/or poor > >installation methods. > > > >The most common cause of permanent damage to to ports is due to incorrect > >installation of cables (NT1 to Ethernet ports is a good one that comes up > >a lot). > > > >In switching the most common problems are duplex mismatches. Usually due > >to a misunderstanding of what duplex setting do. > > > >These are just some considerations there are heaps more. Most are easily > >avoided but difficult to diagnose. An understanding of the fundamentals > >involved can avoid disaster. > > > >Just as a beat up on all. I work in an environment where we supply Telco > >type services and IP connectivity to thousands (this figure is an > >understatement). A part of my job is to troubleshoot client connections > >to our access servers. I can often go for a week or two handling about 10 > >faults or more per day without finding a fault in the configuration of the > >access servers, connections to the access servers and/or the clients > >CPE. This does not leave much but I'll bet most still blame us. I don't > >know how often I will suggest change this setting in your server an all > >will be fine. Bink up it comes and so does the question "what did you do > >at your end to fix my server?" > > > >Incidently the next most common problem I come across is username/password
Passwords (was RE: Electrical and General knowledge
>Ray, > >I think there is a misunderstanding. What he said was non alphanumeric >(something other that letters and numbers). >What I think he means is characters such as !@#$%^&*(), and others. >Alphabetic characters, numbers, and especially mixed case are very much >recommended for security, BUT, I can understand the problems associated with >a user not remembering that he had the 3rd letter of his cat's name >capitalized. > >My $ 0.02 > >Brad Hope it's not getting too far afield, but there are some tricks for getting strong but memorable passwords. The passphrase is good. Remember some natural-language phrase such as "Ciscos that aren't fish aren't kosher" and use the first two letters of each word, capitalizing the first: CiThArFiArKo or even only capitalize the letters that normally would be capitalized: "John Chambers, router jockey" JoCarojo You can strengthen any of these, assuming the strings are varying length, by splitting the passphrase into two and putting one or more numeric digits at the center. Passwords with numbers at the beginning or end are a bit easier to guess. There are other tricks that could work with specific people. Without getting specific, my personal passwords come from a background in biochemistry, and tend to be formulas with deliberate errors in them. The Department of Defense/NSA password management guide at http://www.fas.org/irp/nsa/rainbow/std002.htm is quite well written and gives insights into the relative strength of passwords. > >-Original Message- >From: Ray Mosely [mailto:[EMAIL PROTECTED]] >Sent: Thursday, January 04, 2001 9:14 AM >To: studygroup >Subject: RE: Electrical and General knowledge > > >Sorry, if I understand your comments on passwords, >I must disagree. Username passwords should contain >non-alphabetic characters. This doesn't effect Cisco, >because so far no one seems to have created the right >software to hack the secret password hash. > >However, the Cisco secret password hash is similar to >Microsoft's, and l0pht has long ago created a brute >force hack. I ran the l0pht crack on my userlist 2 >months ago. > >The only passwords that were NOT cracked were mine and >my student worker's. Both had non-alphabetic characters. > >Ray Mosely >CCNA, MCSE > >-Original Message- _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Passwords (was RE: Electrical and General knowledge
Pedantic comment in line. ""Howard C. Berkowitz"" <[EMAIL PROTECTED]> wrote in message news:p05001943b67a45feb3c2@[63.216.127.98]... > >Ray, > > > >I think there is a misunderstanding. What he said was non alphanumeric > >(something other that letters and numbers). > >What I think he means is characters such as !@#$%^&*(), and others. > >Alphabetic characters, numbers, and especially mixed case are very much > >recommended for security, BUT, I can understand the problems associated with > >a user not remembering that he had the 3rd letter of his cat's name > >capitalized. > > > >My $ 0.02 > > > >Brad > > Hope it's not getting too far afield, but there are some tricks for > getting strong but memorable passwords. > > The passphrase is good. Remember some natural-language phrase such as > > "Ciscos that aren't fish aren't kosher" > > and use the first two letters of each word, capitalizing the first: > > CiThArFiArKo > > or even only capitalize the letters that normally would be capitalized: > > "John Chambers, router jockey" > > JoCarojo Howard - Your jockey's fallen at the second hurdle, but I get the idea I think ;-) Some of us have trouble remembering our date of birth - MCMLXIV > > You can strengthen any of these, assuming the strings are varying > length, by splitting the passphrase into two and putting one or more > numeric digits at the center. Passwords with numbers at the beginning > or end are a bit easier to guess. > > There are other tricks that could work with specific people. Without > getting specific, my personal passwords come from a background in > biochemistry, and tend to be formulas with deliberate errors in them. > > The Department of Defense/NSA password management guide at > http://www.fas.org/irp/nsa/rainbow/std002.htm is quite well written > and gives insights into the relative strength of passwords. > > > >-Original Message- > >From: Ray Mosely [mailto:[EMAIL PROTECTED]] > >Sent: Thursday, January 04, 2001 9:14 AM > >To: studygroup > >Subject: RE: Electrical and General knowledge > > > > > >Sorry, if I understand your comments on passwords, > >I must disagree. Username passwords should contain > >non-alphabetic characters. This doesn't effect Cisco, > >because so far no one seems to have created the right > >software to hack the secret password hash. > > > >However, the Cisco secret password hash is similar to > >Microsoft's, and l0pht has long ago created a brute > >force hack. I ran the l0pht crack on my userlist 2 > >months ago. > > > >The only passwords that were NOT cracked were mine and > >my student worker's. Both had non-alphabetic characters. > > > >Ray Mosely > >CCNA, MCSE > > > >-Original Message- > > _ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Passwords (was RE: Electrical and General knowledge
>Gareth Hinton" <[EMAIL PROTECTED]> observed Pedantic >comment in line. Pedantic? I fall, wounded, cursing the stars and my fate. The black skies laugh at me and chastise me with thunderbolts. The floggers of the Elder Gods fall on me, but I am humiliated to find they use wet noodles. As the American truckers would say, that's a big oops, good buddy. I shall emulate Master Ridley and be of good cheer, as my typo lights a fire that shall never be put out. > >""Howard C. Berkowitz"" <[EMAIL PROTECTED]> wrote in message >news:p05001943b67a45feb3c2@[63.216.127.98]... >> >Ray, >> > >> >I think there is a misunderstanding. What he said was non alphanumeric >> >(something other that letters and numbers). >> >What I think he means is characters such as !@#$%^&*(), and others. >> >Alphabetic characters, numbers, and especially mixed case are very much >> >recommended for security, BUT, I can understand the problems associated >with >> >a user not remembering that he had the 3rd letter of his cat's name >> >capitalized. >> > >> >My $ 0.02 >> > >> >Brad >> >> Hope it's not getting too far afield, but there are some tricks for >> getting strong but memorable passwords. >> >> The passphrase is good. Remember some natural-language phrase such as >> >>"Ciscos that aren't fish aren't kosher" >> >> and use the first two letters of each word, capitalizing the first: >> >>CiThArFiArKo >> >> or even only capitalize the letters that normally would be capitalized: >> >> "John Chambers, router jockey" >> > > JoCarojo JoChrojo I stand in humble correction. > >Howard - Your jockey's fallen at the second hurdle, but I get the idea I >think ;-) > >Some of us have trouble remembering our date of birth - MCMLXIV > >> >> You can strengthen any of these, assuming the strings are varying >> length, by splitting the passphrase into two and putting one or more >> numeric digits at the center. Passwords with numbers at the beginning >> or end are a bit easier to guess. >> >> There are other tricks that could work with specific people. Without >> getting specific, my personal passwords come from a background in >> biochemistry, and tend to be formulas with deliberate errors in them. >> >> The Department of Defense/NSA password management guide at >> http://www.fas.org/irp/nsa/rainbow/std002.htm is quite well written >> and gives insights into the relative strength of passwords. > > > _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]