• IPRouting in Heterogeneous Environment by Sumit Kasera, K.R. K. Mohan and Ashutosh Bisht (Presented at ITUT seminar on "Internet Protocol", Bangalore, March, 2000.)

Abstract: Terrestrial IP routing architectures are based on hop-by-hop forwarding paradigm, which has worked well for almost four decades now. However, in a heterogeneous environment where satellite-based networks co-exist with terrestrial networks, a modified routing scheme is necessary. This is because of two reasons, 1) satellite links have low bandwidth and high latency, and 2) satellite-based networks are usually much more meshy, as against a hierarchical or partial-mesh topology of terrestrial networks. This calls for tackling issues like a) reducing routing updates over low-bandwidth satellite link, and b) reducing convergence time. This paper analyses such issues, which crop up in the design of a routing scheme for a heterogeneous environment. The basic goal of this paper is to propose and analyses three routing approaches namely 1) distributed control approach, 2) centralized control approach and 3) hybrid control approach. The suggested routing approaches are compared with regards to route convergence time (for distance vector protocols) and routing traffic overhead (for link state protocols).

A Survey of Lossless Data Compression Technique by Sumit Kasera and Navita Jain

Abstract: Way back in October 1948, an article written by Claude Shannon titled “A Mathematical Theory of Communication” was published in the Bell Lab Technical Journal. A landmark event, this article laid the fundamentals of “Information theory”. In the next five decades or so, the field of information theory has graduated into a big research area and is now practically known as the “Science of Compression”. Compression is essentially a means to reduce the number of bits required to store and transfer information. Compression manifests itself in the form of data compression, speech compression and image compression among others. In this paper, we survey the currently available techniques to compress data. Among the techniques available, two categories are distinctly identifiable. These two categories are lossless compression and lossy compression. In this paper, we limit ourselves to lossless data compression techniques. 

• ATM SVC Signaling Stack: Implementation Guidelines by Nishit Narang and Sumit Kasera

Abstract: ATM is a Virtual Circuit based technology and requires establishment of an end-to-end connection prior to data transfer. This process of connection setup is done using the procedures of signaling. Both ITU-T and the ATM-Forum provide standards for this purpose. This paper provides some insight into the ATM SVC Signaling standards and its implementation. To achieve this end, this paper is organized as follows. Section 1 provides a brief overview of the ATM signaling. Section 2 details about the relevant ATM Standards. The following section talks about the inherent complexities in the ATM standards. Section 4 provides implementation guidelines for the ATM SVC Signaling stack. It also provides for a mechanism to handle some of the complexities mentioned in section 3. Section 5 suggests certain modifications to the standards to make the implementation simple and efficient. Finally, Section 6 concludes the paper.
 
• AAL2 Signaling: A White Paper by Sumit Kasera, Anil Sinha, Kuldeep Singh, and Pitambar Sahoo
Abstract: The communication world is in a state of flux with rapid technological advancements, both in wireline as well as in wireless domain. In wireline domain, TCP/IP has become the de-facto networking protocol suite. ATM technology, which came into existence around a decade back, had to be mostly contented to live under the shadows of the former. However, certain killer applications like Voice over DSL and 3G wireless as brought ATM back into prominence. In order to support these applications, there have been a lot of standardization efforts by ITU-T and ATM Forum. The AAL2 signaling standard is one of the steps in this direction. This standard provides the ability to dynamically establish and release AAL2 channels over existing ATM VCs.  This standard is quite often viewed as an extension of ATM signaling protocol, which is actually not the case. This white paper clears all doubts on AAL2 signaling.
 
Voice over ATM with special focum on AAL2 Signaling: A presentation by Sumit Kasera (Presented at ATM Forum seminar on "Broadband Networking", Delhi, August, 2001.)

 
Timer Management Mechanism by Amit Jha, Deepak Rathore, and Sumit Kasera

Abstract: Stack entities require timer services from the Operating System. This service can be for message retransmission, thread/process synchronization and for various other time-related services. The goal of this paper is to design an Operating System Interface in the form of Operating System Wrapper (OSW) between the Stack entity and the Operating System that can provide the required timer-related service. The OSW hides the details of underlying Operating System from calling Stack entity. The Stack entity uses APIs provided by OSW to use timer facilities of underlying System. This papers covers requirements of timer module and constraints imposed by the Stack entity. In the appendix, it discusses how time is maintained on Linux platform. The design for Linux Implementation is covered. It also contains user manual, which shows sample implementation timer daemon developed.