Transcript Mobile-IP (more in Chapter-11)

Wireless Mobile IP
CCRI ENGR 1500
CCRI
J. Bernardini
1
Mobile IP Components
MN – Mobile Node (VMD)
FA – Foreign Agent (MAP)
HA – Home Agent (MAP)
AAP – Authoritative Access Point
MAP – Mobile IP Access Point (MN)
VMD – Visiting Mobile Device (MN)
COA – Care-of-Address
HAN – Home Agent Network
FAN – Foreign Agent Network
CN – Correspondent Node
CCRI
J. Bernardini
2
Subnets and Mobile IP
• Subnets provide many advantages:
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make network management easier
Subnets reduce broadcasts
Subnets provide security
Subnets use subnet masks (255.255.255.0)
• WLAN subnets creates problems for roaming devices
• Example:
– 192.146.118.20 /24 can seamlessly roam within 192.146.118.x /24
– Note /24 is a 255.255.255.0 subnet mask
– 192.146.118.20 /24 can not seamlessly roam within 202.165.200.x /24
without changing the IP address
• Mobile IP offers a solution
– 192.146.118.20 can roam as a “guest” on the 202.165.200.x network
CCRI
J. Bernardini
3
Mobile IP Devices
• Visiting Device
– Some APs support Mobile IP and Visiting devices
• Mobile IP Access Point
– Performs all Mobile IP services
• Home Agent
– Visiting devices home router
– Tunnels packets from “visited” network to “visiting” device
• Authoritative Access Point (AAP)
– Uses a subnet map to track all home “visiting” devices
• Foreign Agent
– A router the is the attachment point for “visiting” devices
– Tunnels packets to the Home Agent for the “visiting” device
CCRI
J. Bernardini
4
Mobile IP Process - Discovery
Mobile IP
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3-Step Process
1-Discovery
2-Registration
MN – Mobile Node
FA – Foreign Agent
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HA – Home Agent
3-Tunneling
1- Mobile Node (MN) gets address from Home Agent (HA)
2- MN moves to Foreign Agent (FA ) network
3- MN discovers FA or solicits for an agent.
4- MN gets Care-of-Address (COA) from FA
CCRI
J. Bernardini
5
Mobile IP Process - Registration
Mobile IP
3-Step Process
1-Discovery
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2-Registration
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3-Tunneling
MN – Mobile Node
FA – Foreign Agent
HA – Home Agent
CN – Correspondent Node
5- MN send registration request to FA
6- FA checks request, adds MN to pending list
10- FA checks reply and adds MN to visitor list and
relays reply to MN
7- FA relays request to HA
11-FA creates a routing entry and tunnel to HA
8- HA checks request and creates a mobile binding
12- MN check reply and creates a tunnel to the HA
9- HA sends registration reply to FA
Through the FA
CCRI
J. Bernardini
6
Mobile IP- Tunneling and Packet
Forwarding
MN – Mobile Node
FA – Foreign Agent
HA – Home Agent
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CN – Correspondent Node
COA- Care-of-Address
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13- Correspondent Node (CN) sends packet to MN and is routed to HA
14- HA intercepts packets and tunnels to the FA using the COA
15- FA relays the packets to the MN
CCRI
J. Bernardini
7
Mobile Node Movement
CCRI
J. Bernardini
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