DNS updates during handoff with IP Diversity.

Contexts in source publication

Context 1

... crucial part is when LM tries to identify an MH in its relatively newer point of attachment after a handoff. Any location query before updating the LM might result in an incorrect IP address. Sec IV illustrates the problem in detail. The IP Diversity exploited by SIGMA enables the MH to have two IP addresses in the LM during the handover period. Fig. 2 shows the sequence of updates to the ANS by the MH. When the MH reaches the boundary of the overlapping area of the two subnets, it obtains a new IP address and sends an update message to the ANS that stores the new address along with the old one in the DNS, with higher priority being assigned to the old IP address (time t 1 ). Later ...

Context 2

... by the old IP address (time t 2 ). When the MH leaves the overlapping area, it sends an update to the ANS to remove the old IP address (time t 3 ). In the overlapping area (between t 1 and t 3 ), ANS responds to location queries with two IP addresses, the sequence being determined by the position of the MH in the overlapping area as shown in Fig. 2 ...

Context 3

... The effect of the above issue is minimized in the our case as we propose the use of the notion of IP diversity and stores multiple addresses in the DNS during the overlapping area (time t 1 to t 3 in Fig. 2). So, location query failure would occur for SIGMA only if the time taken by the name lookup query response to CN from DNS and connection request from CN to MH is more than the residence time of the MH in the overlapping ...

Context 4

... denote ∆t 1+2 = t 5 − t 4 and ∆t 2+1 = t 6 − t 5 as illustrated in Fig. 2. Here ∆t 1+2 is the time during which an MH is in the overlapping area when the first address has a higher priority, i.e. before the handoff, and ∆t 2+1 is the time DNS as LM CN MH D N S Q u e ry : n a m e lo o k u p D N S R e sp o n se : n a m e -t o -I P C o n n e c ti o n R e q e u s t C o n n e ct io n R e sp o n se spent by the MH ...