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Clocking E1


I have a ip network with 100's of E1 3662 and 3631 router they are connected via E1's the SDH box or MUX is a nortel NE whats the Ideal Clocking configuration for VWIC G.703 E1's



If i make the clocking line-line will it derive the clocking from the Line meaning will it get it from SPE??? pls explain

Is the SDH equipment(Nortel MUX TN16XE) transparent to my clocking

In most world DCN Networks whats the Clocking config used can u name some telco's(SP's) who use the config

Pls do not point me to links to cisco site as they are pretty useless


Amit Singh


Re: Clocking E1

As per my knowledge, E1 VWICs are not supported on Cisco 3660 platforms.

To Configure controller E1 to specify the clock source.The command is Router(config-controller)# clock source {line [primary] | internal}. The line keyword specifies that the clock source is derived from the active linerather than from the free-running internal clock. This is the default setting and is generally more reliable. When both ports are set to line clocking with no primary specification, port 0 is the default primary clock source and port 1 is the default secondary clock source. When both ports are set to line and one port is set as the primary clock source, the other port is by default the backup or secondary source and is loop-timed. If one port is set to clock source line or clock source line primary and the other is set to clock source internal, the internal port recovers clock from the clock source line port if the clock source line port is up. If it is down, then the internal port generates its own clock. If both ports are set to clock source internal, there is only one clock sourceinternal.

Hope this information is useful to you!!!!

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