1 Sideseadmed (IRT0040) loeng 5/2010 Avo

2 IMS with IPv6 Multi-country/Multi-operator SIP-connectivity network Client, Public IPv6 address 1 Client, Public IPv6 address 2 Public IP-routing domain (inter-operator connections) SIP Prox y SIP Signaling: A’s address = Public IPv6 Addr 1 Media from B to A: Sent to Public IPv6 Addr 1

3 Terminology (1) Home Agent (HA) Mobile Host (MH) Foreign Agent (FA) HNFN

4 Terminology (2) Similar to cellular. Mobile Node (MN or MH): node changing its PoA. Correspondent Host (CH). Home Network (HN) and Foreign Network (FN).

5 Terminology (3) Mobility Agents: –Home Agent (HA): router on MN’s HN that tunnels datagrams to MH when away and keeps MH’s current location info. –Foreign Agent (FA): router on foreign network; delivers datagrmas to MH while on FN. Home Address (HoA) and Care-of Address (CoA): –HoA: MH’s permanent address on HN. –CoA: MH’s temporary address on FN.

6 Mobile-IP: Basic Operation MH normally uses its home address HoA. When MH visits a foreign network, –Registration with FA. Discover mobile agent and CoA. –Registration with HA. Binding update (HoA -> CoA). Communicating with MN: use HoA. HA forwards packet from HoA to CoA.

7 Discovering Agents Agents periodically beacon advertisements

8 Agent Discovery Agent advertisement (beaconing): –Mobile agent broadcast agent advertisement at regular intervals (“I am here”). Agent solicitation: –MH can poll (“anyone here?”). –Mobile agent responds to poll.

9 Discovering Agents MH polls; agent responds.

10 Agent Advertisement Allow for the detection of mobility agents. Follows ICMP router advertisement message. Let the MH know whether the agent is a HA, or a FA. List one or more available care-of addresses. Inform the MN about special features provided by FA. –Example: Alternative encapsulation techniques, header compression.

11 Registration

12 Registering When away, MH registers its CoA with HA (binding update). Binding: (HoA->CoA) –Binding has a lifetime. Registration process –MH sends a registration request with CoA. –HA authenticates request. –HA approves or disapproves the request. –HA adds necessary information to its routing table. –HA sends registration reply back to MH.

13 Tunneling HA tunnels datagrams destined to MH when MH is away. –Datagrams sent to MH, intercepted by HA and tunneled to its CoA. Tunnel terminates at MH CoA (either the MH or the FA).

14 Tunneling Tunneled Data Packet HA keeps binding between MH and FA SRC

15 Encapsulation Tunneling requires encapsulation. –Sending the original packet (CH->MH) in another packet (HA->CoA). Default encapsulation mechanism: –IP-within-IP (tunnel). –Tunnel header: new IP header inserted by the tunnel source (home agent). –Destination IP: CoA

16 Mobile IP Basic Operation Entities –Mobile host, home agent, foreign agent, corresponding host Discovering Care-of Addresses –Agent advertisements Registering Care-of Address –Security Tunneling to Care-of Address –IP-within-IP encapsulation

17 Tunneling in Mobile IP

18 Mobile IPv6 Mobility support in IPv6 (RFC 3775) Mobile node (MN) is a mobile device with an IPv6 home address Correspondent node (CN) is a computer with which mobile node communicates using its home address. Home Agent (HA) helps MN to manage its mobility: –Mobile node can always be reached at its home address, regardless of its point of attachment (care-of address) to the Internet. –Connections made with home address survive movement between different IP networks.

19 Mobile IPv6 addressing IP addresses act as both an identifier for a node and as a locator. Mobile IPv6 separates the identity, home address of mobile node from its locator, known as care-of address (CoA). Without Mobile IPv6 MN can not use its home address for sending and receiving packets when it is outside its home network. Mobile IPv6 uses IP-IP tunneling to create a virtual network between its CoA and HA, so that MN always appears to be in its home network.

20 Reverse Tunneling IPv6 in IPv6 tunnel is used for delivering traffic to and from home address of MN via HA. HA uses proxy neighbor discovery to redirect packets on home link destined to home address of MN to its own link layer address. HA keeps track of the care-of address of MN to deliver packets to MN. Tunnel IPv6 hdr (CoA –HA)IPv6 hdr (HoA-CN) Data

21 Mobile IPv6 operation Router solicitation Binding Update Proxy ND for HoA Binding Ack. Tunnel Router Advertisement MN forms Care-of address

22 Route in Mobile IPv6 Tunneling of traffic between MN and CN via home agent is not efficient. –HA is a potential bottleneck –Extra routing hop increases network latency Route optimization (RO) allows MN and CN to communicate directly MN sends a BU to CN. MN and CN use home address option and routing header, type 2 to send packets to each other. Route optimization is secured using return routability protocol.

23 Mobile IPv6 Implementations Windows –MS Research implementation MN, CN, HA –MS CN implementation for Win XP –Elmic software: embedded MN Linux –MIPL (Helsinki University of Technology): MN/CN/HA –Elmic software: embedded MN Symbian: MN Cisco: HA Nokia: HA

24 Mobile IPv6 extensions Localized mobility management –Hierarchical Mobile IPv6 –Fast Mobile IPv6 Context transfer to new router: Context transfer protocol Early discovery of new router: Candidate access router discovery protocol

25 Network Mobility

26 NEMO (RFC 3963) Operation IP IP tunnel Network a:1:: Network a:: Network b::

27 IPv4 Mobility vs IPv6 Mobility functionIPv4 (RFC3344)IPv6 (RFC 3775) addressing32 bit addresses128 bit addresses Home addressOne home addressA globally routable Home Address (HoA)and a link local HoA Care-of-AddressVia agent discovery, DHCP or manual config Stateless Address Autoconfig, DHCP manual config or

28 IPv4 Mobility vs IPv6 Mobility functionIPv4 (RFC 3344)IPv6 (RFC 3775) Movement detectionAgent Discovery through Foreign Agent IPv6 Router Discovery CoA (Care of Address) Foreign Agent CoA and co-located CoA CoA’s are ALL co- located. No Foreign Agents needed Dynamic Home Agent Address Discovery (DHAAD) Directed broadcast. Returns separate replies from all HA’s to the MN (Mobile Node) Anycast addressing. Returns a single reply to the MN

29 IPv4 Mobility vs IPv6 Mobility functionIPv4 (RFC 3344)IPv6 (RFC 3775) Data packet delivery to MN Tunnel routingTunnel routing and source routing with IPv6 routing headers Decapsulation of data packets sent to MN’s CoA Foreign Agent decapsulates MN itself decapsulates Link layer neighbour address discovery ARPIPv6 neighbour discovery; decoupled from any given link layer.

30 Lingid ment

31 Mobile IP _workshop2_module3_final_animated.ppt

32 Mobile IPv6 Mobile IPv6: RFC 3775 Securing Mobile IPv6 MN-HA signaling: RFC 3776 Hierarchical MIPv6: RFC 4140 Fast Mobile IPv6: RFC 4068 Context transfer protocol: RFC 4067 Candidate access router discovery protocol: RFC 4068 Network Mobility (NEMO) Basic Support Protocol: RFC 3963