SHIP: Performance Reference: “SHIP mobility management hybrid SIP-HIP scheme” So, J.Y.H.; Jidong Wang; Jones, D.; Sixth International Conference on May 2005 Page(s): Digital Object ID /SNPD-SAWN

2005/12/62 Background In the current wireless networks, wireless management can be handled in Data Link Layer or Physical Layer In the 4G wireless networks, handover between different wireless networks can’t be handle by the old method Network Layer and Application Layer are the most suitable layers for the mobility management

2005/12/63 Session Initiation Protocol An Application Layer protocol used to create or tear down multimedia session Can perform mobility support that is independent of the underlying wireless technology and network layer element in the Application Layer The best choice for real-time application only

2005/12/64 Session Initiation Protocol (cont.) Application Layer protocol will get lowest priority in networking model and so a long delay in hand-off will occur Doesn’t support mobility in other connections that aren’t created under SIP Hybrid SIP and other protocols are considered by many research changing addresses or ports, adding a media stream, deleting a media stream, etc.  re-INVITE

2005/12/65 Host Identify Protocol Introduces a new namespace - Host Identity and a new layer - Host Identity Layer HI (Host Identifier) is represented with a 128- bit long HIT (Host Identity Tag) HI that is a cryptographic key of a public- private key-pair will be used to identify node and endpoint instead of IP addresses PrefixHash

2005/12/66 Host Identity Layer

2005/12/67 Host Identify Protocol (cont.) 4-way handshake Diffie-Hellman authenticated key is exchanged during handshake Diffie-Hellman key is used to establish a pair of IPsec ESP (Encapsulated Security Payload) SAs (Security Associations) between hosts

2005/12/68 4-way handshake of HIP InitiatorResponder I1: trigger exchange Select pre-computed R1 R1: puzzle, D-H, key, sig Check sigRemain stateless Solve puzzle I2: solution, D-H, {key}, sig Compute D-HCheck puzzle Check sig R2: sig Check sigCompute D-H Security Context established ESP protected messages

2005/12/69 HIP packet structure Packets traveling in the network doesn’t contain the actual HI information Next HeaderHeader Length0Packet TypeVER.RES.1 ChecksumControls Sender's Host Identity Tag Receiver's Host Identity Tag HIP Parameters

2005/12/610 HIP packet structure (cont.) Arriving packets is identified and mapped to the correct SA using the SPI (Security Parameter Index) value in the IPsec header

2005/12/611 HIP - mobility DNS may not be able to update immediately RVS (Rendezvous Server) is similar to the HA in Mobile IP DNS will carry the mapping between FQDN and the corresponding RVS IP addresses Direct mapping between HI and IP addresses of the host will be stored in RVS

2005/12/612 4-way handshake of HIP via RVS

2005/12/613 HI-IP Mapping A.DNS only B.DNS with RVS

2005/12/614 HIP - Mid-session mobility Send the UPDATE package with REA (Readdress) parameter to the other nodes and its RVS Critical scenarios  Double jump problem  IP address changes during the 4-way handshakes  Solved by involving RVS

2005/12/615 SHIP (Hybrid SIP-HIP) Pre-session  SIP location server will return the HI address instead of an IP address  Until the mapping of the SIP, URI and HI address is changed, no updates are required in the SIP location server Mid-session  HIP UPDATE package with REA parameter will be sent to the corresponding host  SIP doesn’t need to send re-INVITE message

2005/12/616 SHIP Procedures

2005/12/617 Handoff Signaling Analysis D handoff = D dhcp + D notice D notice = O handoff =

2005/12/618 Handoff Signaling Parameters SymbolMeaningTypical value D dhcp Delay of DHCP address assignment1s D notice Delay for MH to notify CH of its new location BW wired Bandwidth of wired links100Mb/s BW wireless Bandwidth of wireless links11Mb/s (802.11b) L wired Latency of wired links0.5ms L wireless Latency of wireless links2ms HDistance between MH and CH in hops LIP packet length of notice message TsAverage time for which MH remains in a subnet

2005/12/619 Handoff Signaling Delay SIP =140 bytes; HIP = 80 bytes; Mobile IP = 56 bytes

2005/12/620 Handoff Signaling Delay (cont.) Hybrid SIP-Mobile IP need to use HA to re- direct the packet until the SIP re-INVITE progress is completed  Two handoff processes are needed in one handoff Handoff only needs to be processed once in SHIP

2005/12/621 Handoff Signaling Overhead H=50

2005/12/622 Handoff Signaling Overhead (cont.) Overhead of hybrid SIP-Mobile IP scheme will be the sum of the Mobile IP and SIP as two handoff processes are needed SHIP has been shown to outperform than hybrid SIP-Mobile IP

2005/12/623 Conclusion This paper has proposed SHIP for future IP based wireless networks SHIP avoids the re-INVITE message in SIP and therefore, its signaling message is smaller SHIP also provides multi-homing support, which does not exist in hybrid SIP-Mobile IP

2005/12/624 Reference Session Initiation Protocol  RFC-3261 HIP Working Group (Internet-Draft)  Host Identity Protocol - Extended Abstract  Ericsson Research, NomadicLab (WWRF8bis) Mobility support in wireless Internet  Wireless Communications (IEEE)