Internet Core Protocols: The Definitive Guide

Media-Related Issues

Since IP packets are sent inside of media-specific frames, there can be problems with some network media that will manifest when used with IP packets. For example, some network managers have reported problems with network infrastructure equipment such as Ethernet hubs and switches that have problems dealing with full-sized (1500-byte) packets. In those situations, you will need to use ICMP to probe the network for delivery problems through equipment that is acting suspicious.

One way to do this is to send incrementally larger ICMP Echo Request messages to other devices on those networks, testing to see where they stop working. If the hub or switch stops forwarding data to all of the attached devices after a certain point, then it is possible that the device itself could be eating the packets. However, it is also entirely possible that the problem lies with your own equipment. In order to verify your suspicions, you should test connectivity using another system with a different network adapter (since your adapter may be the true culprit). However, if only one or two devices fail to respond, then the problem is likely to be with the adapters or drivers in use with those systems.

In addition, some network managers have reported problems with wide-area networking equipment that interprets some bit patterns from the IP packet as test patterns. In those cases, the WAN equipment may eat the packets. The packets that are most problematic are those that contain long sequences ...