The 4x4 Approach, a MobileIP Variation
• An Address Mobility Solutions
• Extension of MobileIP
The 4x4 Approach, a MobileIP Variation
Mobile IP - Concerns
• Mobile devices
– Addresses assigned by region is not applicable
– Device location
• Integration into current infrastructure
– Compatibility
– Scalability
– Transparency
The 4x4 Approach, a MobileIP Variation
Key Terms
• Mobile node (MN)
– Mobile end user device/system communication with CN
– Communicates with CN
• Correspondent node (CN)
– Fixed (for this topic) or mobile device/system
– Communicates with a MN
The 4x4 Approach, a MobileIP Variation
Key Terms Cnt’d
• Foreign agent (FA)
– Node/router MN is connected to
– Boasts all network facilities
• Home Network (HA)
– MN’s IP address belongs to this network
– A router/node
The 4x4 Approach, a MobileIP Variation
MobileIP - Background
• Keeps old IP address
• Adds an additional address
– Care of address (COA)
– Two types:
* Foreign agent-based (COA is FA)
* Colocated (Uses Tunneling, COA is topologically correct)
The 4x4 Approach, a MobileIP Variation
The 4x4 Approach
• Removes unnecessary overhead of MobileIP
• Presumes MN not dependent on FA
• MN able to aquire COA from current subnet
• Optimization Goals:
– Guaranteed delivery, low latency, and low overhead
The 4x4 Approach, a MobileIP Variation
4x4 Approach - Concepts
• MN-to-CN (OUT)
– Four packet delivery options
• CN-to-MN (IN)
– An additional four packet delivery options
• Delivery selection options
– IN/OUT selection not necessarily independent
– session-to-session
– packet-to-packet
The 4x4 Approach, a MobileIP Variation
4x4 Terms
• s
– Encapsulated source
• d
– Encapsulated source
• S
– Source
• D
– Destination
The 4x4 Approach, a MobileIP Variation
4x4 IN packet options
IN Strategy
s
d
S
D
Notes
Incoming
Indirect
Encapsulated
(IN-IE)
IP address COA
of HA
of MN
IP
address
of CN
Home IP
address of
MN
1. Highest overhead
2. Guaranteed Delivery
3. Uses tunneling
4. CN can be mobility unaware
Incoming Direct
Encapsulated
(IN-DE)
IP address COA
of CN
of MN
IP
address
of CN
Home IP
address of
MN
1. CN is mobility aware
2. No tunneling
Incoming Uses
Home Address
(IN-DH)
-
-
IP
address
of CN
Home IP
address of
MN
1. No encapsulation
2. Only if intervening routers have
no security constraints
3. MN & CN on common subnet
Incoming Direct
Uses Temporary
Address
(IN-DT)
-
-
IP
address
of CN
COA of MN
1. MN cannot receive packets sent
to its original address
2. Short-term communication
The 4x4 Approach, a MobileIP Variation
4x4 OUT packet options
IN Strategy
s
d
S
D
Notes
Outgoing
Indirect
Encapsulated
(IN-IE)
COA
IP address
of MN of HA
Home IP
address of
MN
IP
address
of CN
1. Highest overhead
2. Guaranteed Delivery
3. No ingress filtering
4. CN can be mobility unaware
Outgoing Direct
Encapsulated
(IN-DE)
COA
IP address
of MN of HA
Home IP
address of
MN
IP
address
of CN
1. CN is mobility aware
2. No tunneling
Outgoing Uses
Home Address
(IN-DH)
-
-
Home IP
address of
MN
IP
address
of CN
1. No encapsulation
2. Only if intervening routers have
no security constraints
3. MN & CN on common subnet
Outgoing Direct
Uses Temporary
Address
(IN-DT)
-
-
COA of MN
The 4x4 Approach, a MobileIP Variation
1. MN cannot receive packets sent
to its original address
2. Short-term communication
4x4 Option Set
Note:
(1) Lighter shading indicates compatibility with current standards
(2) Darker shading indicates incompatibility with current standards
The 4x4 Approach, a MobileIP Variation
References
1.
2.
3.
Handout (unknown source), Wireless Internet, Ch4. Page 155 to 189.
Stuart Cheshire and Mary Baker , “Internet Mobility 4x4”. ACM
SIGCOMM 1996, pp. 318-329, August 1996.
https://www.cs.tcd.ie/~htewari/papers/InternetMobility4x4.pdf
http://www.stanford.edu/class/cs444n/handouts/mobile1.ppt
The 4x4 Approach, a MobileIP Variation
A Title
• First
– Sub-First
• Second
– Sub-second
The 4x4 Approach, a MobileIP Variation