Current Research
Interests:
Horizontal handoff is defined as handoff
between same types of network, for example between BSS of cellular
Networks. Traditional handoff algorithms are based on variety of
threshold values such as RSS, SIR (Signal to Interference ratio), CIR
(Carrier to Interference ratio), BLER (block error rate), power budget,
etc. Vertical handoff is a handoff between various technologies such as
WLAN and 3G cellular networks. Vertical handoff can be classified as
Upward Vertical handoff that is moving from smaller networks with high
bandwidth to large network with lower bandwidth. On the other hand,
Downward Vertical handoff is movement from large networks to smaller
networks. Generally handoff decision is based on RSS. If the Vertical
handoff is only executed by measuring RSS then ping pong effects may
cause unnecessary handoffs therefore it may be wise to have multiple
metrics such as RSS, moving velocity as a decision factor. Mobile IP
based Vertical handoff increase signaling cost and Handoff delays.
Vertical handoff is desired since QoS in one network falls below certain
threshold value in terms of certain metrics and it is expected that the
next networks would provide better services
Current Research with
Abstract:
User quest for higher data rates to run
multi media applications while on the move has paved the way for myriad
of cellular and wireless networks emerging in a short span of time. To
get the benefits of all such technologies having diversified
characteristics in terms of data rate, access methods, etc. a user may
roam between these networks. Hence point of attachment changes
frequently and this is called vertical handoff (VHO). Integration of
diversified networks is also one of the major objectives of future
networks commonly called 4GI (Fourth Generation Integration). Two
mobility protocols that is Session Initiation Protocol (SIP) and Mobile
Internet Protocol (MIP) with some limitations, are being implemented
standalone and in combination as mechanisms to implement vertical
handoff. It is desired to propose a mechanism to implement SIP and MIP
in concerned networks jointly to yield optimized results and overcome
their limitations during VHO.
Past Research:
• Implementation of RFID to
improve Law & Order situation in Karachi
