Sideseadmed IRT 0040 loeng 52010 Avo avotslr ttu

Sideseadmed (IRT 0040) loeng 5/2010 Avo avots@lr. ttu. ee 1

Client, Public IPv 6 address 1 IMS with IPv 6 Multi-country/Multi-operator SIP-connectivity network SIP Prox y SIP Signaling: A’s address = Public IPv 6 Addr 1 SIP Prox y Public IP-routing domain (inter-operator connections) Media from B to A: Sent to Public IPv 6 Addr 1 Client, Public IPv 6 address 2 2

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

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

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 (Ho. A) and Care-of Address (Co. A): – Ho. A: MH’s permanent address on HN. – Co. A: MH’s temporary address on FN. 5

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

Discovering Agents periodically beacon advertisements 7

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. 8

Discovering Agents MH polls; agent responds. 9

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. 10

Registration 11

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

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

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

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

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 16

Tunneling in Mobile IP 17

Mobile IPv 6 • Mobility support in IPv 6 (RFC 3775) • Mobile node (MN) is a mobile device with an IPv 6 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. 18

Mobile IPv 6 addressing • IP addresses act as both an identifier for a node and as a locator. • Mobile IPv 6 separates the identity, home address of mobile node from its locator, known as care-of address (Co. A). • Without Mobile IPv 6 MN can not use its home address for sending and receiving packets when it is outside its home network. • Mobile IPv 6 uses IP-IP tunneling to create a virtual network between its Co. A and HA, so that MN always appears to be in its home network. 19

Reverse Tunneling • IPv 6 in IPv 6 tunnel is used for delivering traffic to and from home address of MN via HA. Tunnel IPv 6 hdr (Co. A –HA) IPv 6 hdr (Ho. A-CN) Data • 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. 20

Mobile IPv 6 operation Tunnel Binding Ack. Proxy ND for Ho. A Binding Update Router Advertisement Router solicitation MN forms Care-of address 21

Route in Mobile IPv 6 • 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. 22

Mobile IPv 6 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 23

Mobile IPv 6 extensions • Localized mobility management – Hierarchical Mobile IPv 6 – Fast Mobile IPv 6 • Context transfer to new router: Context transfer protocol • Early discovery of new router: Candidate access router discovery protocol 24

Network Mobility 25

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

IPv 4 Mobility vs IPv 6 Mobility function IPv 4 (RFC 3344) IPv 6 (RFC 3775) addressing 32 bit addresses 128 bit addresses Home address One home address A globally routable Home Address (Ho. A)and a link local Ho. A Care-of-Address Via agent discovery, Stateless Address DHCP or manual Autoconfig, DHCP config manual config or 27

IPv 4 Mobility vs IPv 6 Mobility function IPv 4 (RFC 3344) IPv 6 (RFC 3775) Movement detection Agent Discovery through Foreign Agent IPv 6 Router Discovery Co. A (Care of Address) Foreign Agent Co. A’s are ALL coand co-located Co. A 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 28

IPv 4 Mobility vs IPv 6 Mobility function IPv 4 (RFC 3344) IPv 6 (RFC 3775) Data packet delivery Tunnel routing to MN Tunnel routing and source routing with IPv 6 routing headers Decapsulation of data packets sent to MN’s Co. A MN itself decapsulates Foreign Agent decapsulates Link layer neighbour ARP address discovery IPv 6 neighbour discovery; decoupled from any given link layer. 29

Lingid http: //en. wikipedia. org/wiki/Mobile_IP http: //tools. ietf. org/html/rfc 3344 http: //en. wikipedia. org/wiki/Mobile_IP http: //en. wikipedia. org/wiki/Mobility_manage ment http: //www. iec. org/online/tutorials/tmn/ 30

Mobile IP http: //www. ietf. org/rfc 3344. txt? number=3 344 http: //www. ietf. org/rfc 3775. txt? number=3 775 http: //www. hznet. de/ipv 6/mipv 6 -intro. pdf http: //www. ipv 6. org. uk/workshop/slides/ipv 6 _workshop 2_module 3_final_animated. ppt 31

Mobile IPv 6 • Mobile IPv 6: RFC 3775 • Securing Mobile IPv 6 MN-HA signaling: RFC 3776 • Hierarchical MIPv 6: RFC 4140 • Fast Mobile IPv 6: RFC 4068 • Context transfer protocol: RFC 4067 • Candidate access router discovery protocol: RFC 4068 • Network Mobility (NEMO) Basic Support Protocol: RFC 3963 32