RE: 56K vs 64K
Could you post a link or somewhere to get this info. I have been looking and cannot find anything. I remember covering this in BCRAN and would like to go through it again. Having to do with the serial lines and the sampling rate, bit robbing etc. SF/ESF AMI/B8ZS etc. If you have a link to this info I would love to read it over again. -Original Message- From: Howard C. Berkowitz [mailto:[EMAIL PROTECTED]] Sent: Wednesday, December 20, 2000 1:02 PM To: [EMAIL PROTECTED] Subject: Re: 56K vs 64K High-level view: Remember there are multiple levels in the "T1" world. I'm carefully avoiding "layer" If anyone starts trying to force this into OSI layering, I will start to mutter, "This is a .44 magnum, the most powerful handgun in the world. I can't remember if I've fired 5 or 6 rounds. Feeling lucky, punk?" :-) The lowest level is the electrical/optical signal format Next, you have bit stream encoding (AMI, B8ZS, etc.) Next, you have framing (SF, ESF) And with voice services, you have call control (CCS, CAS, etc.) Bruce Williams [EMAIL PROTECTED] wrote, On a T1 line what is the difference between 56K and 64K. If I am correct I believe that 56K uses bit stuffing to stuff the 8th bit of every timeslot with a 1 to fulfill the ones density requirement. However, this would not be necessary with B8ZS line coding, right because B8ZS will not allow 8 consecutive zeroes anyway. You're right about B8ZS, but 56K (and, for that matter, 48K) was introduced at a time when AMI was extremely common. Now if that is true, why would you use 56K on a B8ZS coded T1 circuit and if those timeslots are cross-connected to a 64K line or vice versa, wont that cause errors because the two clock rates are expecting different things in the 8th bit. I would appreciate any comments at all on this subject. But the DS0 sees a 64 KBPS stream and doesn't inherently expect any meaning in any particular bit. Bit meaning does come up at a higher level when used for telco signaling, as with CAS and CCS. I didn't even _think_ of the acronym CCIE while writing the body of this message. No ciscos were scaled, finned, or fried in its preparation. _ 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: 56K vs 64K
Could you post a link or somewhere to get this info. I have been looking and cannot find anything. I remember covering this in BCRAN and would like to go through it again. Having to do with the serial lines and the sampling rate, bit robbing etc. SF/ESF AMI/B8ZS etc. If you have a link to this info I would love to read it over again. Unfortunately, I don't know of an online link. The Cisco University voice courseware lacked it, and I tended to do this material at the whiteboard. I go into it to a reasonable extent in my new book, WAN Survival Handbook (Wiley). -Original Message- From: Howard C. Berkowitz [mailto:[EMAIL PROTECTED]] Sent: Wednesday, December 20, 2000 1:02 PM To: [EMAIL PROTECTED] Subject: Re: 56K vs 64K High-level view: Remember there are multiple levels in the "T1" world. I'm carefully avoiding "layer" If anyone starts trying to force this into OSI layering, I will start to mutter, "This is a .44 magnum, the most powerful handgun in the world. I can't remember if I've fired 5 or 6 rounds. Feeling lucky, punk?" :-) The lowest level is the electrical/optical signal format Next, you have bit stream encoding (AMI, B8ZS, etc.) Next, you have framing (SF, ESF) And with voice services, you have call control (CCS, CAS, etc.) Bruce Williams [EMAIL PROTECTED] wrote, On a T1 line what is the difference between 56K and 64K. If I am correct I believe that 56K uses bit stuffing to stuff the 8th bit of every timeslot with a 1 to fulfill the ones density requirement. However, this would not be necessary with B8ZS line coding, right because B8ZS will not allow 8 consecutive zeroes anyway. You're right about B8ZS, but 56K (and, for that matter, 48K) was introduced at a time when AMI was extremely common. Now if that is true, why would you use 56K on a B8ZS coded T1 circuit and if those timeslots are cross-connected to a 64K line or vice versa, wont that cause errors because the two clock rates are expecting different things in the 8th bit. I would appreciate any comments at all on this subject. But the DS0 sees a 64 KBPS stream and doesn't inherently expect any meaning in any particular bit. Bit meaning does come up at a higher level when used for telco signaling, as with CAS and CCS. I didn't even _think_ of the acronym CCIE while writing the body of this message. No ciscos were scaled, finned, or fried in its preparation. _ 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: 56K vs 64K
Here is a link to a White Paper on T-1 basics. It covers with moderate detail what you are wanting. http://www.ttc.com/downloads/white_papers/t1_tn.pdf There are many other White Papers on the page I found the this one on that might be of interest to everyone. http://www.ttc.com/technical_resources/white_papers/index.html -Scott Brenner CCNP/CCDP -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Christopher Larson Sent: Thursday, December 21, 2000 5:47 AM To: 'Howard C. Berkowitz'; [EMAIL PROTECTED] Subject: RE: 56K vs 64K Could you post a link or somewhere to get this info. I have been looking and cannot find anything. I remember covering this in BCRAN and would like to go through it again. Having to do with the serial lines and the sampling rate, bit robbing etc. SF/ESF AMI/B8ZS etc. If you have a link to this info I would love to read it over again. -Original Message- From: Howard C. Berkowitz [mailto:[EMAIL PROTECTED]] Sent: Wednesday, December 20, 2000 1:02 PM To: [EMAIL PROTECTED] Subject: Re: 56K vs 64K High-level view: Remember there are multiple levels in the "T1" world. I'm carefully avoiding "layer" If anyone starts trying to force this into OSI layering, I will start to mutter, "This is a .44 magnum, the most powerful handgun in the world. I can't remember if I've fired 5 or 6 rounds. Feeling lucky, punk?" :-) The lowest level is the electrical/optical signal format Next, you have bit stream encoding (AMI, B8ZS, etc.) Next, you have framing (SF, ESF) And with voice services, you have call control (CCS, CAS, etc.) Bruce Williams [EMAIL PROTECTED] wrote, On a T1 line what is the difference between 56K and 64K. If I am correct I believe that 56K uses bit stuffing to stuff the 8th bit of every timeslot with a 1 to fulfill the ones density requirement. However, this would not be necessary with B8ZS line coding, right because B8ZS will not allow 8 consecutive zeroes anyway. You're right about B8ZS, but 56K (and, for that matter, 48K) was introduced at a time when AMI was extremely common. Now if that is true, why would you use 56K on a B8ZS coded T1 circuit and if those timeslots are cross-connected to a 64K line or vice versa, wont that cause errors because the two clock rates are expecting different things in the 8th bit. I would appreciate any comments at all on this subject. But the DS0 sees a 64 KBPS stream and doesn't inherently expect any meaning in any particular bit. Bit meaning does come up at a higher level when used for telco signaling, as with CAS and CCS. I didn't even _think_ of the acronym CCIE while writing the body of this message. No ciscos were scaled, finned, or fried in its preparation. _ 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] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: 56K vs 64K
See also: http://www.larscom.com/support/multimedia/acrobat/access-t/access-t.pdf Watch the wrap. Pages 9 to 19 -Original Message- From: Scott Brenner [mailto:[EMAIL PROTECTED]] Sent: Thursday, December 21, 2000 9:46 AM To: Christopher Larson; 'Howard C. Berkowitz'; [EMAIL PROTECTED] Subject: RE: 56K vs 64K Here is a link to a White Paper on T-1 basics. It covers with moderate detail what you are wanting. http://www.ttc.com/downloads/white_papers/t1_tn.pdf There are many other White Papers on the page I found the this one on that might be of interest to everyone. http://www.ttc.com/technical_resources/white_papers/index.html -Scott Brenner CCNP/CCDP -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Christopher Larson Sent: Thursday, December 21, 2000 5:47 AM To: 'Howard C. Berkowitz'; [EMAIL PROTECTED] Subject: RE: 56K vs 64K Could you post a link or somewhere to get this info. I have been looking and cannot find anything. I remember covering this in BCRAN and would like to go through it again. Having to do with the serial lines and the sampling rate, bit robbing etc. SF/ESF AMI/B8ZS etc. If you have a link to this info I would love to read it over again. -Original Message- From: Howard C. Berkowitz [mailto:[EMAIL PROTECTED]] Sent: Wednesday, December 20, 2000 1:02 PM To: [EMAIL PROTECTED] Subject: Re: 56K vs 64K High-level view: Remember there are multiple levels in the "T1" world. I'm carefully avoiding "layer" If anyone starts trying to force this into OSI layering, I will start to mutter, "This is a .44 magnum, the most powerful handgun in the world. I can't remember if I've fired 5 or 6 rounds. Feeling lucky, punk?" :-) The lowest level is the electrical/optical signal format Next, you have bit stream encoding (AMI, B8ZS, etc.) Next, you have framing (SF, ESF) And with voice services, you have call control (CCS, CAS, etc.) Bruce Williams [EMAIL PROTECTED] wrote, On a T1 line what is the difference between 56K and 64K. If I am correct I believe that 56K uses bit stuffing to stuff the 8th bit of every timeslot with a 1 to fulfill the ones density requirement. However, this would not be necessary with B8ZS line coding, right because B8ZS will not allow 8 consecutive zeroes anyway. You're right about B8ZS, but 56K (and, for that matter, 48K) was introduced at a time when AMI was extremely common. Now if that is true, why would you use 56K on a B8ZS coded T1 circuit and if those timeslots are cross-connected to a 64K line or vice versa, wont that cause errors because the two clock rates are expecting different things in the 8th bit. I would appreciate any comments at all on this subject. But the DS0 sees a 64 KBPS stream and doesn't inherently expect any meaning in any particular bit. Bit meaning does come up at a higher level when used for telco signaling, as with CAS and CCS. I didn't even _think_ of the acronym CCIE while writing the body of this message. No ciscos were scaled, finned, or fried in its preparation. _ 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] _ 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: 56K vs 64K
I think, and I am certainly not certain as I do not remember exactly, but I believe you get 56k on super-frame and 64k on extended super frame and not the line coding. Please correct me if I am wrong. I believe that super frame uses a robbed bit scheme and esf does not? I know this was covered in BCRAN and I found it very interesting and revealing but cannot remember the whole explanation in it's entirety. -Original Message- From: Bruce Williams [mailto:[EMAIL PROTECTED]] Sent: Wednesday, December 20, 2000 12:18 PM To: [EMAIL PROTECTED] Subject: 56K vs 64K On a T1 line what is the difference between 56K and 64K. If I am correct I believe that 56K uses bit stuffing to stuff the 8th bit of every timeslot with a 1 to fulfill the ones density requirement. However, this would not be necessary with B8ZS line coding, right because B8ZS will not allow 8 consecutive zeroes anyway. Now if that is true, why would you use 56K on a B8ZS coded T1 circuit and if those timeslots are cross-connected to a 64K line or vice versa, wont that cause errors because the two clock rates are expecting different things in the 8th bit. I would appreciate any comments at all on this subject. -- Bruce Williams [EMAIL PROTECTED] _ 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: 56K vs 64K
High-level view: Remember there are multiple levels in the "T1" world. I'm carefully avoiding "layer" If anyone starts trying to force this into OSI layering, I will start to mutter, "This is a .44 magnum, the most powerful handgun in the world. I can't remember if I've fired 5 or 6 rounds. Feeling lucky, punk?" :-) The lowest level is the electrical/optical signal format Next, you have bit stream encoding (AMI, B8ZS, etc.) Next, you have framing (SF, ESF) And with voice services, you have call control (CCS, CAS, etc.) Bruce Williams [EMAIL PROTECTED] wrote, On a T1 line what is the difference between 56K and 64K. If I am correct I believe that 56K uses bit stuffing to stuff the 8th bit of every timeslot with a 1 to fulfill the ones density requirement. However, this would not be necessary with B8ZS line coding, right because B8ZS will not allow 8 consecutive zeroes anyway. You're right about B8ZS, but 56K (and, for that matter, 48K) was introduced at a time when AMI was extremely common. Now if that is true, why would you use 56K on a B8ZS coded T1 circuit and if those timeslots are cross-connected to a 64K line or vice versa, wont that cause errors because the two clock rates are expecting different things in the 8th bit. I would appreciate any comments at all on this subject. But the DS0 sees a 64 KBPS stream and doesn't inherently expect any meaning in any particular bit. Bit meaning does come up at a higher level when used for telco signaling, as with CAS and CCS. I didn't even _think_ of the acronym CCIE while writing the body of this message. No ciscos were scaled, finned, or fried in its preparation. _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
