1. Mobile Communications-Network Protocols/Mobile IP
Presented by: Indhra Priya Shanmugam
Submitted To: Professor Ivan Stojmenovic

2. WHY MOBILE IP
The node must change its IP address whenever it changes its point of attachment.
(impossible for a node to maintain transport and higher layer connections when the node changes location)
Host-specific routes must be propagated throughout much of the Internet.
(does not scale very well)
Indhra P Shanmugam, Wireless Networks and Mobile Computing

3. Mobile IP is an Internet Engineering Task Force (IETF) standard communications protocol that is designed to allow mobile device users to move from one network to another while maintaining a permanent IP address.
Indhra P Shanmugam, Wireless Networks and Mobile Computing

4. system in the home network of the MN, typically a router
Mobile Node (MN)
system (node) that can change the point of connection to the network without changing its IP address
Home Agent (HA)
system in the home network of the MN, typically a router
registers the current location of the MN, tunnels IP datagram's to the COA
Foreign Agent (FA)
system in the current foreign network of the MN, typically a router
De-tunnels and delivers datagram's to the MN
Care-of Address (COA)
address of the current tunnel end-point for the MN (at FA or MN)
actual location of the MN from an IP point of view
can be chosen, e.g., via DHCP
Correspondent Node (CN)
communication partner
Indhra P Shanmugam, Wireless Networks and Mobile Computing

5. HOW MOBILE IP WORKS 2 1 6 3 4 5
Indhra P Shanmugam, Wireless Networks and Mobile Computing

6. Agent Advertisement Registration Tunneling FUNCTIONS OF MOBILE IP
The main functions of Mobile IP are:
Agent Advertisement
Registration
Tunneling
Indhra P Shanmugam, Wireless Networks and Mobile Computing

7. AGENT ADVERTISEMENT Agent Discovery
MN detect whether its has moved and it is connected to Home Network (HN) or Foreign Network (FN)
Agent Advertisement
Routers broadcast an advertisement to links to offer services
ICMP Router Advertisement Message.
Two types of Message
Agent Solicitation
Indhra P Shanmugam, Wireless Networks and Mobile Computing

8. Agent Solicitation
When a MN needs information about Foreign agents, it broadcasts Solicitation messages
Foreign Agents respond with a router advertisement message directly to the MN.
Type: 10 Code: 0 Reserved: 0 Checksum: 0
Indhra P Shanmugam, Wireless Networks and Mobile Computing

9. AGENT ADVERTISEMENT type = 16 length = 6 + 4 * #COAs
R: registration required
B: busy, no more registrations
H: home agent
F: foreign agent
M: minimal encapsulation
G: GRE encapsulation
r: =0, ignored
T: FA supports reverse tunneling
reserved: =0, ignored
Indhra P Shanmugam, Wireless Networks and Mobile Computing

10. REGISTRATION MN communicate their reachability to HA
MN request service when visiting FN
MN inform HA the current COA
Deregister
Indhra P Shanmugam, Wireless Networks and Mobile Computing

11. REGISTRATION CRTITERIA
There are 2 types Registration Procedures:
Through Foreign Agent
Directly with Home Agent
If MN registering a Foreign Agent COA , then register via FA
If MN got an advertisement from FA, then register via Foreign Agent
If MN has returned to HA, it registers directly with its Home Agent
If MN is using Co-located COA, it registers naturally with its HA
Indhra P Shanmugam, Wireless Networks and Mobile Computing

12. REGISTRATION MESSAGE
Registration messages in Mobile IP use the User Datagram Protocol (UDP).
There are two registration Message:
Registration Request
Registration Response
Indhra P Shanmugam, Wireless Networks and Mobile Computing

13. AUTHENTICATION
To allow additional security for registration process, Mobile IP defines registration extensions:
Mobile-Home Authentication extension
Mobile-Foreign Authentication extension
Foreign-Home Authentication extension
Each extension includes SPI and IP address that contains secret information needed to compute others
The default algorithm uses MD5(Message Digest) to authenticate the request and response messages
Indhra P Shanmugam, Wireless Networks and Mobile Computing

14. AUTHENTICATION FORMAT
Secret key is used both – Prefix and Suffix to data
SPI selects authentication algorithm, mode and secret key used in authenticator
SENDER = Message + algorithm +secret key
RECEIVER = Message Received + algorithm to be used + Secret Key
IF Sender = Receiver ( Authenticated)
Indhra P Shanmugam, Wireless Networks and Mobile Computing

15. TUNNELING
After successful Registration, Mobile IP requires encapsulation to deliver datagram
The encapsulation and decapsulation methods are called tunneling
When data transfer, Home agent intercepts the data sent to MN and tunnels them to the COA of MN
There are 3 main Tunneling algorithm:
IP-in-IP Encapsulation (Default)
Minimal Encapsulation
Generic Record Encapsulation (GRE)
Indhra P Shanmugam, Wireless Networks and Mobile Computing

16. IP-IN-IP ENCAPSULATION
IP datagram is encapsulated within another IP datagram. Data is carried as payload
Outer header is added before existing IP header
Additional headers can be added for security reasons
Indhra P Shanmugam, Wireless Networks and Mobile Computing

17. MINIMAL ENCAPSULATION
Devised to avoid redundancy from IP-in-IP
Datagram should be not fragmented before encapsulation
Minimal Forwarding Header is used
No additional IP header is added
Indhra P Shanmugam, Wireless Networks and Mobile Computing

18. GRE ENCAPSULATION
It is more general method. Also used for many other Protocols
Indhra P Shanmugam, Wireless Networks and Mobile Computing

19. REVERSE TUNNELING
Tunneling starts at the HA and is decapsulated by either FA or MN (end)
Decapsulation depends on type of COA
Foreign Agent COA – FA
Co-located COA – MN
When MN sends message to CN, the process is called Reverse Tunneling
Indhra P Shanmugam, Wireless Networks and Mobile Computing

20. ROUTE OPTIMIZATION
One of the problem with Mobile IP – Triangle Routing
To overcome this, Route Optimization is implemented
Indhra P Shanmugam, Wireless Networks and Mobile Computing

21. ROUTE OPTIMIZATION OVERVIEW
There are 4 operations in Route Optimization:
Binding Caches:
It maintains COA of mobile nodes and directly tunnels data to MN
Manage Smooth Handoff:
When MN moves from one FA to another
Registration Keys:
Securely perform operations for handoff and authentication
Using Special Tunnels:
To perform tunneling in special cases
Indhra P Shanmugam, Wireless Networks and Mobile Computing

22. ROUTE OPTIMIZATION MESSAGE FORMATS
There are 4 Message Formats:
Binding Warning Message:
To warn MN that it has no cache entry
When MN detunnels and is not in current FA
Binding Request Message:
Request for MN’s current mobility binding
Binding Update Message:
Update or notify MN’s current mobility binding
Binding Acknowledge Message:
Acknowledge the receipt of update message
Indhra P Shanmugam, Wireless Networks and Mobile Computing

23. MOBILE IP - ROUTE OPTIMIZATION
Indhra P Shanmugam, Wireless Networks and Mobile Computing

24. SECURITY IN MOBILE IP Network Security in Mobile IP is important.
Compromise in Security may lead too:
Unauthorized access
Disclosure of information
Unreliability
Denial of Service
Corruption of Data
Indhra P Shanmugam, Wireless Networks and Mobile Computing

25. SECURITY ENHANCEMENTS
Security can be maintained in Mobile IP using:
Confidentiality
Authentication
Non-Repudiation
Integrity
Authorization
Security in IP
Firewall
Indhra P Shanmugam, Wireless Networks and Mobile Computing

26. FUTURE OF MOBILE IP Mobile IP is the Voice and Data of Future
It is currently used in:
3G Wireless, CDMA, GSM
VOIP Services
VPN
CISCO
WLAN
IOS
Campus Mobility
Metro Mobility
Indhra P Shanmugam, Wireless Networks and Mobile Computing

27. Indhra P Shanmugam, Wireless Networks and Mobile Computing

28. Question – 1: In Mobile IP Protocol, Explain with Diagram how the Registration Process takes place: a) When Mobile Node (MN) is in Home Network (HN) b) When Mobile Node (MN) is in Foreign Network (FN)
Indhra P Shanmugam, Wireless Networks and Mobile Computing

29. Question – 2: In Mobile IP Protocol,
a) What are the three main Tunneling algorithm?
b) Which approach is used to solve the Triangle Routing Problem and explain its message Format ?
Answer :
a) The three main Tunneling algorithm are :
IP-In-IP Encapsulation
Minimal Encapsulation
GRE Encapsulation
b) Route Optimization. Its message format are :
Binding Warning Message
Binding Request Message
Binding Update Message
Binding Acknowledgement Message
Indhra P Shanmugam, Wireless Networks and Mobile Computing

30. Question – 3: The given diagram explains how datagrams are transferred from Correspondent Node (CN) to Mobile Node (MN) in the current Foreign Agent (FA) using Mobile IP Protocol.
Consider that the Mobile Node moved from Foreign Agent Old to Foreign Agent New. Using Route Optimization, Complete the following diagram, explaining how a Mobile Node can move from FA old to FA new.
Indhra P Shanmugam, Wireless Networks and Mobile Computing

31. Answer:
Indhra P Shanmugam, Wireless Networks and Mobile Computing

32. REFERENCES
C. Perkins, Mobile IP: Design Principles and Practice, Addison-Wesley Longman
Handbook of Wireless Networks and Mobile Computing, Edited by Ivan Stojmenovic
Stefan Raab and Madhavi W. Chandra, Mobile IP Technology and Applications
Abdul Sakib Mondal, Mobile IP – Present State and Future
Dr.-Ing. Jochen Schiller,
Indhra P Shanmugam, Wireless Networks and Mobile Computing

33. Indhra P Shanmugam, Wireless Networks and Mobile Computing