The network layer is the most vulnerable part of TCP/IP in terms of its functionality. In most cases, network layers are where the Internet protocol and internet control message protocol are situated. The use of ICMP is to give reliable information, while IP is applied in virtually every communication within the internet system. In the process of transmitting packets of data, it identifies the route in which it should be transmitted to the specified destination; and when they receive information, it also locates its identity in terms of where they belong, thus acting as the right tool for data identification.
It must be noted that the network layer does not have much concern on whether the packet data is delivered or not, or whether the data received are in order of when and how they were sent. Basically, IP takes simple steps in the transmission of data information, identifying how it transmits the message in the intended destination, even though it does not have direct control of its security per se. A good illustration of the privacy and security concerns is in this part of communication which lacks wire security as in the case with the traditional physical wired communication systems of the telephony. This simply means that delivering a telephone message has no security as one can hardly authenticate the recipient or sender of the voice messages.
This is because it typically uses the public internet and the TCP/IP protocol stack, which do not provide the physical wire in its network layer. This weakness has increased opportunities and frequencies of covert channel attacks, particularly through its network layer section. It’s thus a continuous concern for the internet and security experts who intend to get the weakness sorted out to increase internet communication safety.