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ECS LAN cable to CCPC length limited (long known bug):

A hardware implementation problem with the CCPC causes the Ethernet network to fail if the cable exceeds a length of 20m. Do not use the ECS CCPC LAN port without inserting a HUB acting as a driver for the Ethernet connection. In wall plugs the cable length extends up to 100m which is clearly causing the network to fail.

MEP assembled with wrong Ethernet frames due to too long timeout (11.7.2006):

The raw data transport format defines the 16-bit Identification bit to be used with the 15-LSBs of the L0-EvCnt of the first event in the MEP plus the MSB set to 0 for L0 event data. 15-bit counters overflow in this network region at an event rate of 1.11 MHz every 29 ms. This identification is used for IP packet assembly on the IP stack. In the lab use, packet loss on the Ethernet network causes identical Ethernet frames to occur at the earliest after 29 ms. The time out for not received packets is set normally to 30s. We reduced the rate of this problem by using a 16-bit MEP counter for the Identification - it reduced at high MEP factor the occurrence of this problem to a few per day. You can avoid this problem if you work in a network without packet loss.

 

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