Question

Compare different types of transmission errors that can occur in wireless and wired networks

Answer 1

Packet loss due to congestion: Congestion may appear from time to time even in carefully designed networks. The packets buffers of a router are filled and the router can not forward the packets fast enough because the sum of the input rates of packets destined for one output link is higher than the capacity of the output link. The only thing a router can do in this situation is to drop packets. This kind of packet loss can occur in both wireless and wired networks. Packet loss due to random loss The random loss is due to bit corruption and link errors. In wired network, the transmission error rate (10-10 -10-12) is generally very low so that it can be neglected. However it is not true for the wireless network (10-2 -10-4 ). Packet loss due to burst loss The burst loss may be initiated by signal fading. Prolonged uncontrolled channel interference can lead to correlated packet losses. Yet it generally occurs over a very short duration, leading a loss of several consecutive segments at a time. In an infrastructure network, when a mobile host is moved from the coverage of a base station to another, all subsequent communications are routed via the new base station and the handoff process is completed. However the packet may be lost as they are routed to the old station during the process of the handoff. Therefore a handoff event can initiate a burst loss event. In ad hoc network, same situation can happen. During to the mobility of the mobile host, the network connectivity and the network topology can change. The transmission path for a traffic flow may be affected. Some time is necessary to complete the rerouting process for the traffic flow. Thus some packet belong to the same traffic flow may be lost during the process. As a result, a burst loss event occurs in this case.