A transparent virtual machine monitor level packet compression network service

Packet compression is a well-known technique for improving the performance of low speed networks such as WANs. This technique is also effective in networks with a high cost per transmitted byte, namely wireless networks. Most implementations of this technique as a network service, like IPComp, are not transparent and require modifications either to applications or to operating systems. Some other implementations of this technique as a network service, e.g. WANProxy, run as user space processes that impose extra overhead due to unnecessary packet hooking mechanisms, involving frequent switches between user and kernel spaces. This paper presents a transparent packet compression network service using virtualization technology. This service transparently compresses network packet payloads and reduces communication overhead of applications running inside virtual machines. This service requires no modifications to applications, operating systems or virtual machine monitors. In addition, it has no extra overhead for switching between user and kernel spaces, because it is implemented as a configurable kernel module that can be activated or deactivated dynamically. A proof-of-concept transparent packet compression service has been implemented on Xen hypervisor. Evaluation results show the feasibility of development and dynamic configuration of such a transparent packet compression network service. Results also show approximately 25% improvement in network performance of applications over slow or congested links. In addition, the results show that this service can tremendously reduce transmitted bytes over high cost networks like wireless networks, in a transparent manner.