Re: Clocking Question
Hi, just by making a clocking command in a router doesnt make a router DCE device.when u connect two routers back to back, one router will become the dce depending on the cable pins connected to it. in cisco cables you normally get two diiffrent cables for dte and dce seperately. u can verify the interface(whether its DTE or DCE) by typing "sh controllers serial x". but when u conect to the csu..automatially the csu will become the DCE and provide the clocking.. Rajagopal Iyengar wrote: > Hello Group, > My Name is Rajgopal and I am based in Bombay,India.I have a question for you > guys. > I have read in the CCNA 2.0 Exam Certification guide by Wendell Odom that a > DTE is the equipment that receives the Clocking information from a DCE which > is the device that sends the clocking information for sync Links and at the > same time he also says that a serial line comming from the ISP is connected > to a CSU/DSU which in turn is connected to your serial port in the router > and the CSU/DSU is the device which gives the clocking information for the > sync links. > Whereas the ICRC book says that by default the Cisco router is a DTE > equipment and the minute we implement the clocking command on a particular > serial interface then it becomes a DCE device. > Correct me if I am wrong but for the clocking command to work on the > enterprise side we have to enable the clocking command.Then does that > interface become a DCE ??And if it becomes a DCE then doesn't it defy the > rule that a DTE is connected to a DCE ?? > The ICRC book also says that in case if you don't have a CSU/DSU u have to > use a back to back cable to connect the 2 routers and the interface on which > u implement the clocking command becomes a DCE interface.But don't u think > that its the ISP which gives u the clocking information?? > > Please enlighten me on this subject as soon as possible because I have my > CCNA exam on the 21st of Sept,2000 and I would like to be clear on as many > concepts as possible. > > Many thanks and please help me out. > > Regards, > Raj. > > P.s U can email me on the above mentioned address. > > _ > Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. > > Share information about yourself, create your own public profile at > http://profiles.msn.com. > > **NOTE: New CCNA/CCDA List has been formed. For more information go to > http://www.groupstudy.com/list/Associates.html > _ > UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html > FAQ, list archives, and subscription info: http://www.groupstudy.com > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] **NOTE: New CCNA/CCDA List has been formed. For more information go to http://www.groupstudy.com/list/Associates.html _ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Clocking Question
I think it can be summarised as such if the modem is providing clocking to the router then modem is the DCE device router is the DTE device whereas as in the case of the lab scenario where we do not have a modem then we need to join two routers together to simulate a WAN link then for the virtual WAN link to work one of the routers need to provide the clocking . The router which provides the clocking is the DCE device while the router which receives the clocking is the DTE device . To find which router is the one suppose to provide the clocking do a sh controllers s0 or s1 to check which is running DCE or DTE hope this helps Jason -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Rajagopal Iyengar Sent: Tuesday, September 19, 2000 11:58 AM To: [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: Clocking Question Hello Group, My Name is Rajgopal and I am based in Bombay,India.I have a question for you guys. I have read in the CCNA 2.0 Exam Certification guide by Wendell Odom that a DTE is the equipment that receives the Clocking information from a DCE which is the device that sends the clocking information for sync Links and at the same time he also says that a serial line comming from the ISP is connected to a CSU/DSU which in turn is connected to your serial port in the router and the CSU/DSU is the device which gives the clocking information for the sync links. Whereas the ICRC book says that by default the Cisco router is a DTE equipment and the minute we implement the clocking command on a particular serial interface then it becomes a DCE device. Correct me if I am wrong but for the clocking command to work on the enterprise side we have to enable the clocking command.Then does that interface become a DCE ??And if it becomes a DCE then doesn't it defy the rule that a DTE is connected to a DCE ?? The ICRC book also says that in case if you don't have a CSU/DSU u have to use a back to back cable to connect the 2 routers and the interface on which u implement the clocking command becomes a DCE interface.But don't u think that its the ISP which gives u the clocking information?? Please enlighten me on this subject as soon as possible because I have my CCNA exam on the 21st of Sept,2000 and I would like to be clear on as many concepts as possible. Many thanks and please help me out. Regards, Raj. P.s U can email me on the above mentioned address. _ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. Share information about yourself, create your own public profile at http://profiles.msn.com. **NOTE: New CCNA/CCDA List has been formed. For more information go to http://www.groupstudy.com/list/Associates.html _ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] **NOTE: New CCNA/CCDA List has been formed. For more information go to http://www.groupstudy.com/list/Associates.html _ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Clocking Question
Rajagopal, I've worked in the telecom field for many years and DCE and DTE can be very confusing. DCE and DTE primarily depends upon your point of perspective. If you have a modem, CSU or DSU that generate clock to a particular piece of equipment, they are all called a DCE device. The piece of equipment receiving the clock is called a DTE device. Now let me confuse you. If that piece of equipment passes the clock to another device, that interface on that piece of equipment is DCE while the device receiving the clock is called DTE. For example; CSU provides T1 clock to a multiplexer and the multiplexer provides clock to 24 external channel devices. The CSU is a DCE device. The multiplexer interface receiving the clock is a DTE device. The 24 multiplexer interfaces providing clock to the external channels are DCE interfaces while the external channel devices that receive the clock are DTE interfaces. You can daisy chain this out to as many devices as you want but you get the p! icture. I hope this helps. MIke >>> "Rajagopal Iyengar" <[EMAIL PROTECTED]> 09/18 11:57 PM >>> Hello Group, My Name is Rajgopal and I am based in Bombay,India.I have a question for you guys. I have read in the CCNA 2.0 Exam Certification guide by Wendell Odom that a DTE is the equipment that receives the Clocking information from a DCE which is the device that sends the clocking information for sync Links and at the same time he also says that a serial line comming from the ISP is connected to a CSU/DSU which in turn is connected to your serial port in the router and the CSU/DSU is the device which gives the clocking information for the sync links. Whereas the ICRC book says that by default the Cisco router is a DTE equipment and the minute we implement the clocking command on a particular serial interface then it becomes a DCE device. Correct me if I am wrong but for the clocking command to work on the enterprise side we have to enable the clocking command.Then does that interface become a DCE ??And if it becomes a DCE then doesn't it defy the rule that a DTE is connected to a DCE ?? The ICRC book also says that in case if you don't have a CSU/DSU u have to use a back to back cable to connect the 2 routers and the interface on which u implement the clocking command becomes a DCE interface.But don't u think that its the ISP which gives u the clocking information?? Please enlighten me on this subject as soon as possible because I have my CCNA exam on the 21st of Sept,2000 and I would like to be clear on as many concepts as possible. Many thanks and please help me out. Regards, Raj. P.s U can email me on the above mentioned address. _ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. Share information about yourself, create your own public profile at http://profiles.msn.com. **NOTE: New CCNA/CCDA List has been formed. For more information go to http://www.groupstudy.com/list/Associates.html _ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] **NOTE: New CCNA/CCDA List has been formed. For more information go to http://www.groupstudy.com/list/Associates.html _ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Clocking Question
My understanding is that the CSU/DSU usually acts as both a DCE device and a DTE device. Although depending on how you configure it, it can be any combination. Usually you configure it to provide clocking to your equipment (router) so it is DCE to the router. And, you usually configure it to accept clocking from the line coming from the service provider, so it is DTE to the network. So, normally the router is working with its default setting - DTE. If you have routers in a test lab, or a back to back cable running under the floor or something, you don't need a CSU/DSU, and you can configure one router to provide clocking to the other. Hope that helps, Mike >Hello Group, >My Name is Rajgopal and I am based in Bombay,India.I have a question for >you >guys. >I have read in the CCNA 2.0 Exam Certification guide by Wendell Odom that a >DTE is the equipment that receives the Clocking information from a DCE >which >is the device that sends the clocking information for sync Links and at the >same time he also says that a serial line comming from the ISP is connected >to a CSU/DSU which in turn is connected to your serial port in the router >and the CSU/DSU is the device which gives the clocking information for the >sync links. >Whereas the ICRC book says that by default the Cisco router is a DTE >equipment and the minute we implement the clocking command on a particular >serial interface then it becomes a DCE device. >Correct me if I am wrong but for the clocking command to work on the >enterprise side we have to enable the clocking command.Then does that >interface become a DCE ??And if it becomes a DCE then doesn't it defy the >rule that a DTE is connected to a DCE ?? >The ICRC book also says that in case if you don't have a CSU/DSU u have to >use a back to back cable to connect the 2 routers and the interface on >which >u implement the clocking command becomes a DCE interface.But don't u think >that its the ISP which gives u the clocking information?? > >Please enlighten me on this subject as soon as possible because I have my >CCNA exam on the 21st of Sept,2000 and I would like to be clear on as many >concepts as possible. > >Many thanks and please help me out. > >Regards, >Raj. > >P.s U can email me on the above mentioned address. _ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. Share information about yourself, create your own public profile at http://profiles.msn.com. **NOTE: New CCNA/CCDA List has been formed. For more information go to http://www.groupstudy.com/list/Associates.html _ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
