Mobile ip Overview Chuan-Ming liu Computer Science and Information Engineering National Taipei University of Technology Spring 04
Mobile IP – Overview Chuan-Ming Liu Computer Science and Information Engineering National Taipei University of Technology Spring ‘04
Mobile ip discussion overview o Will coⅴer: o Why IP routing breaks under mobility o Mobile ipva basics o Some low-level protocol details(message formats, headers, etc.) o Lots more detail in the specifications(see RFC)
Mobile IP Discussion Overview Will cover: ⚫ Why IP routing breaks under mobility ⚫ Mobile IPv4 basics ⚫ Some low-level protocol details (message formats, headers, etc.) Lots more detail in the specifications (see RFC)
Why Mobile Ip? o Laptop computing o Wireless technologies o Mobility v.S. Portability o Making mobility transparent to applications
Why Mobile IP? Laptop Computing Wireless Technologies Mobility v.s. Portability Making mobility transparent to applications
IP Addresses o Two parts Routing prefix(determined by the netmask) network on which the address resides Host number host on the network 32 bits routing prefix host number
IP Addresses Two parts: ⚫ Routing prefix (determined by the netmask) network on which the address resides ⚫ Host number host on the network routing prefix host number 32 bits
Two-level Addressing o Applications use ip addresses to identify routes by which datagrams may be exchanged between network nodes o applications also use ip addresses to find the endpoints o The delivery of packets consists of o Routing to the destination network o Sending to the host
Two-level Addressing Applications use IP addresses to identify routes by which datagrams may be exchanged between network nodes Applications also use IP addresses to find the endpoints The delivery of packets consists of ⚫ Routing to the destination network ⚫ Sending to the host
Two-level Addressing o Things are different when changing ones point of attachment to the internet o Mobile node mn, or mobile host (MH), in the mobile computing environment may change its point of attachment to the internet say from 140.124.182Xto128.10.7Z
Two-level Addressing Things are different when changing one’s point of attachment to the internet. Mobile node (MN) , or mobile host (MH), in the mobile computing environment may change its point of attachment to the internet, say from 140.124.182.X to 128.10.7.Z
MN140124.182X R 140124.182 Internet 128.107 R 128.10.7Z MN140124182X
R R 140.124.182 128.10.7 Internet MN 140.124.182.X MN 140.124.182.X 128.10.7.Z
What is mobile p o Modification to ip that allows nodes to continue to receive datagrams no matter where they happen to be attached to the Internet o Scalability has been a dominant design factor o Recall that ip can identify a node on the internet uniquely
What is Mobile IP Modification to IP that allows nodes to continue to receive datagrams no matter where they happen to be attached to the internet Scalability has been a dominant design factor Recall that IP can identify a node on the internet uniquely
If no mobile p o Two ways to support mobility o Change IP address whenever it changed its point of attachment o host-specific routes must be propagated throughout the relevant portion of the Internet routing infrastructure o above two approaches are not acceptable
If no Mobile IP Two ways to support mobility ⚫ Change IP address whenever it changed its point of attachment ⚫ Host-specific routes must be propagated throughout the relevant portion of the Internet routing infrastructure Above two approaches are not acceptable
Two Addresses for mobile p Mobile ip solves this by maintaining two addresses One identifies a communication endpoint Chome address o The other locates the mobile computer care-of address
Two Addresses for Mobile IP Mobile IP solves this by maintaining two addresses: ⚫ One identifies a communication endpoint (home address) ⚫ The other locates the mobile computer (care-of address)
