HSN ‘98 ‘ ~ 14, 전주 1 IP over Wireless ATM 김 용 진 한국전자통신연구원

HSN ‘98 ‘ ~ 14, 전주 2 Outline Background Mobile IP IP over ATM Location Management in WATM IP over Wireless ATM

HSN ‘98 ‘ ~ 14, 전주 3 Background Motivation Increase of IP service demands  # of hosts on the Internet has doubled per year  # of web servers has doubled every 20 weeks  From best efforts service to QoS guaranteed real-time multimedia services (-> ATM) Information infrastructure based on ATM technology  Needs for development of new services  Needs for supporting legacy communication services (-> IP) Communication evolution into wired/wireless integrated environment  Rapid increase of mobile phone service users  Needs for mobile multimedia services (-> Mobile ATM)

HSN ‘98 ‘ ~ 14, 전주 4 IP Mobility Support over ATM MIP over ATM = MIP + IPOA Mobility support in IP layer Connectionless oriented mobility support IP over WATM = IPOA + WATM Mobility support in ATM layer Connection oriented mobility support

HSN ‘98 ‘ ~ 14, 전주 5 Mobile IP Internet RFCs RFC 2002 : IP Mobility Support RFC 2003 : IP Encapsulation within IP RFC 2004 : Minimal Encapsulation within IP RFC 2005 : Applicability Statement for IP Mobility Support RFC 2006 : The Definitions of Managed Objects for IP Mobility

HSN ‘98 ‘ ~ 14, 전주 6 Mobility Problems and Solutions Mobility problems A name is a location-independent id An address reflects a host’s point of attachment to the network In IP, DNS(Domain Name System) is used for name-to-address translation In MIP, the binding is a function of time -> IP layer needs mobility control Network layer solution architecture Two-tier addressing  Two internet addresses with each mobile host (Home address, Care-of address)  - Home address for protocol processing  - Care-of address for routing

HSN ‘98 ‘ ~ 14, 전주 7 MIP Components R R Care-of address Home address CN Internet Home network Foreign network MN FA HA MN

HSN ‘98 ‘ ~ 14, 전주 8 Mobility Control Advertisement Registration Request Registration Reply Datagram Tunneled datagram MN Decapsulation Datagram Encapsulation FA HA

HSN ‘98 ‘ ~ 14, 전주 9 Routing Optimization Home network Foreign network f Cache g LD MH S Source Address translation agent Location directory

HSN ‘98 ‘ ~ 14, 전주 10 IP vs. ATM IP Connectionless Currently No QoS Destination based routing Future, scalability Problem Moderate overhead Mobile IP Variable packet size Multicast/broad cast ATM Connection Oriented QoS Support Fast Switching Scalable High overhead for IP over ATM Wireless ATM Fixed packet size Yes but requires VC mesh or MCS

HSN ‘98 ‘ ~ 14, 전주 11 IP over ATM IPOA Paradigm Layered Model Classical IP over ATM LAN Emulation (ATM Forum) (IETF) Multi-protocol over ATM (ATM Forum) Next Hop Resolution Protocol (IETF) Integrated Model I-PNNI (ATM Forum) IP & Tag Switching (IETF)

HSN ‘98 ‘ ~ 14, 전주 12 Characteristics of Layered Model IP overlays ATM with layer 3 (layered routing) ARP (IP, ATM) is required IP routing protocol in IP routers ATM routing protocols are used Modifications in ATM control SW are not required Inefficient multicasting Standardized Specs.

HSN ‘98 ‘ ~ 14, 전주 13 Characteristics of Integrated Model Integrated routing protocol ARP (IP, ATM) is not required ATM routing protocols are not used Modifications in ATM control SW are required Efficient multicasting Standardized Specs. are in progress

HSN ‘98 ‘ ~ 14, 전주 14 Comparison : Route Selection I-PNNI OSPF MPLS PNNI OSPF NHRP Classic OSPF PNNI OSPF IP ATM IP OSPF

HSN ‘98 ‘ ~ 14, 전주 15 Comparison :Internode Communication Protocols Type of communication MPLS NHRP I-PNNI OSPF Routing OSPF /PNNI I-PNNI Signaling TDP, IFMP,... PNNI I-PNNI Address resolution NHRP

HSN ‘98 ‘ ~ 14, 전주 16 IP over WATM (I) IP addr (= AP) --> (ATM visiting_addr = AP) i) IP addr -- ARP -> ATM home_addr -- MC(t) -> ATM visiting_addr ii) IP addr ARP*(t) > ATM visiting_addr

HSN ‘98 ‘ ~ 14, 전주 17 IP over WATM (II) IP Over WATM = IPOA + WATM cf) MIP over ATM NHRP (X) MPLS (X) I-PNNI Mobility Control MC(t) Home agent Foreign agent NHRP MPLS I-PNNI

HSN ‘98 ‘ ~ 14, 전주 18 Location Management in WATM LM enables the network to communicate with MN by managing the information about the location of the MN LM = Mobile tracking + Mobile locating Mobile Tracking Network elements updating procedure about the location of mobile entities Mobile tracking = Mobile registration + updating Mobile Locating The procedure by which a network node determines the location of the MT for the delivery of incoming calls May be executed explicitly prior to call setup or may be an integral part of the call setup procedure

HSN ‘98 ‘ ~ 14, 전주 19 Two Approaches for the LM in WATM Mobile PNNI scheme LR scheme

HSN ‘98 ‘ ~ 14, 전주 20 Mobile PNNI Scheme Extension of the PNNI routing protocol to support MN Use of the PNNI routing protocol for reachability information Scope parameter for the restriction of RI update No explicit “search” procedure prior to call setup Connection setup combined with mobile locating Requires additional routing optimization process

HSN ‘98 ‘ ~ 14, 전주 21 PNNI Routing Protocol Overview Hierarchical peer groups with Peer Group Leaders(PGLs) and Logical Group Nodes(LGNs) Exchange of information for topology, load and reachability by using Protocol Topology State Packet (PTSP) Reachability summarized and advertised by PGLs

HSN ‘98 ‘ ~ 14, 전주 22 PNNI Extension Enhancement of the PNNI routing protocol for the exchange of reachability information of mobile users Three new parameters are defined Scope S is used to set the stop point for reachability information propagation Ancestors-are-sibling level a ij of nodes i and j is the level at which the ancestors of the two nodes i and j belong to the same peer group The neighborhood G i of a node i is defined to include all nodes j such that a ij >= S

HSN ‘98 ‘ ~ 14, 전주 23 Mobile Tracking Mobile registers at switch n New location outside the neighborhood of the old location ? a no < S Send registration to home swtich Send registration to old switch to set a pointer at to the old switch to forward calls to new location Send registration to home switch ; Send registration to old switch to set a pointer at the old switch to forward calls to new location (if home = old, only one registration is needed) YesNo Power on/off registration Registration resulting from a move from mode o to new node n

HSN ‘98 ‘ ~ 14, 전주 24 Connection Setup/Mobile Locating Calls arrives at the origination switch Call arrival was after reachability update is complete Call is routed directly to the mobile Call is routed to the old location and then to the current location of the mobile Call arrival was after reachability update is complete Call is routed to the home switch and then to the current location of the mobile Call is routed to the home switch, then to the old location and finally to the current location of the mobile Call arrival was after home switch receives registration following a move or the home is the old location Called mobile is in its home neighborhood ? a hv >= S Calling party is outside the called mobile’s neighborhood a cv < S Calling party is within the called mobile’s neighborhood a cv >= S No Yes

HSN ‘98 ‘ ~ 14, 전주 25 LR Scheme Application of cellular LR scheme to PNNI-based hierarchical ATM networks Hierarchical LR DBs Scope parameter for the restriction of LR provisioning level Isolate effect for mobility from PNNI routing protocol Explicit “search” procedure prior to call setup

HSN ‘98 ‘ ~ 14, 전주 26 LR Architecture

HSN ‘98 ‘ ~ 14, 전주 27 Mobile Tracking in the LR Scheme Mobile registers at switch Updates are propagated from L th level LR to S th level LR ; Home LR is informed about the current S th level LR. Updated are propagated from L th level LR to a on th level LR at the new neighborhood ; Cancellations are propagated from L th level LR to a on + l th level LR at the old neighborhood. Updates are propagated from L th level LR to S th level LR at the new neighborhood ; Home LR is informed about the new S th level LR ; Cancellations are propagated from L th level LR to S th level LR at the old neighborhood. a on >= S No Yes Power on/off registration at switch n Registration resulting from a move from node o to new node n

HSN ‘98 ‘ ~ 14, 전주 28 Mobile Locating in the LR Scheme Calling party’s switch(c) Called mobile’s current switch(v) Home switch of the called mobile(h) l = I l = S l = L LOCREQ Response

HSN ‘98 ‘ ~ 14, 전주 29 Comparison Item Mobile PNNI LR Address space partition Not required Required Resource allocation for call setup Not optimizedOptimized Application to public network Applicable Not applicable Modification of ATM signaling and routing Required Not required Performance Superior in low CMR Superior in high CMR

HSN ‘98 ‘ ~ 14, 전주 30 Performance & Cost Issues LM cost = Mobile tracking cost + Mobile location cost Mobile tracking (locating) cost = Computational cost (DB access) + Communication cost (signaling & routing) For performance analysis, exact models of network and mobile node are required