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Network Discovery and Selection/Re-selection. OUTLINE. Network Model Use-case Scenario Solution IP Addressing. Network Model. ASN: Access Service Network A ASN contains BSs and ASN-GWs . NAP: Network Access Provider A NAP contains one or more ASNs. NSP: Network Service Provider.
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OUTLINE • Network Model • Use-case Scenario • Solution • IP Addressing
Network Model • ASN: Access Service Network • A ASN contains BSs and ASN-GWs. • NAP: Network Access Provider • A NAP contains one or more ASNs. • NSP: Network Service Provider
Deployment case • NAP Sharing • More than one NSPs shares the same NAP • NAP+NSP
Use-case Scenario • 1.First-time use • 2.Initial network entry • 3.Network Re-entry • The same as handoff within the same WiMAX NAP • 4.MSS transitions across NAP coverage areas • Due to user movement or confounding factor, MSS elects to transition another NAP
Solution • In a WiMAX network, a full network discovery and selection procedure includes four steps: 1.WiMAX NAP Discovery 2.NSP Access Discovery 3.NSP Enummeration and Selection 4.ASN Attachment based on NSP selection • Two WiMAX network selection modes are defined, automatic and manual.
Solution (1) • WiMAX NAP Discovery • An SS/MS detects available NAPs by scanning and decoding DL-MAP of ASN on detected channel. • The most significant 24-bit value of “operator ID” within the “BS ID” parameter in the DL-MAP message is the NAP Identifier. • In NAP+NSP deployment case, NAP identifier shall be identical with NSP identifier. NAP discovery is based on the procedures defined in IEEE Std 802.16-2004 [x1]
Solution (2) • NSP Access Discovery • The SS/MS shall sequentially perform association with each NAP for the purpose of discovering the supported NSPs • The ASN transmits the NSP ID list message no less than once every five seconds. • For SS/MS with configuration information that includes a list of NAP + NSP unitary mappings, WiMAX NAP Discovery of the NAP Identifier is sufficient to provide NAP and NSP.
Solution (3) • NSP Enumeration and Selection • Manaul or Automatic mode • If displayed, NSPs from the list of available NSPs shall be presented in the following order: a) Home NSP b) NSPs in the "User Controlled NSP Identifier list" data file in the SS/MS c) NSPs in the "Operator Controlled NSP Identifier list" data file d) Any other NSP in random order • The signal quality shall not be used as a parameter for NSP Selection
Solution (4) • ASN Attachment based on NSP selection • An SS/MS indicates its NSP selection by attaching to an ASN associated with the selected NSP, and by providing its identity and home NSP domain in form of NAI. • The ASN uses the NAI to determine the next AAA hop to where the MS’s AAA packets should be routed. NAI (Network Access Identifier) Example: • MS_1 uses a normal/root NAI (i.e., user-name@NSP_1.com) • MS_2 needs to construct a decorated NAI (e.g., NSP_4!user-name @NSP_1.com) • [RFC4282]
Solution (5) • NSP Access Discovery(2) and NSP Enumeration(3) and Selection may well occur concurrent to WiMAX NAP Discovery(1). • There is no requirement that an SS/MS discover all NAPs and NSPs. • An SS/MS may stop the discovery process on discovery of a NAP and NSP meeting the SS/MS NSP Enumeration and Selection criteria and proceed to ASN Attachment.
Configuration Information in SS/MSS • User/Operator controlled NAP Identifier list • Determining priority order of performing NSP Access Discovery procedure among if there are more than one available NAP. • User/Operator controlled NSP Identifier list • The lists are used to select a NSP. • NAP/NSP mapping list • Indicating the supported NSPs per NAP • NSP Count • Indicating whether the list of supported NSPs for a NAP is changed • Physical information: • Information useful in NAP Discovery including channel, center frequency, and PHY profile • Network deployment mode • Indicating the Network deployment mode of each NAP, i.e. NAP+NSP mode or NAP sharing mode.
IP Addressing • The functional entity residing in ASN-GW is a DHCP relay. • Functional Decomposition for PoA from Visited NSP • Functional Decomposition for PoA from Home NSP
IP configuration setup • The functional entity residing in ASN-GW is a DHCP relay. • Access authentication: • the network assigning the PoA address is determined.