【精品ppt】magazine文章心得

Magazine文章心得,學號：643430007姓名：蘇彥文,Abstract,A new method to support UMTS WLAN vertical handover using SCTP Interworking techniques and architectures for WLAN 3G integration toward 4G mobile data networks IEEE802.11 roaming and authentication in wireless LAN cellular mobile networks 心得,Magazine 1,A new method to support UMTS WLAN vertical handover using SCTP,Note Abstract,UMTS networks and WLANs Third-generation cellular networks UMTS/WLAN vertical handover problemOverview of Mobile SCTPVERTICAL HANDOVER PROCEDURES,UMTS networks and WLANs,UMTS wide-area connectivity low data rate high mobility WLANshigher data rate low mobility,Third-generation cellular networks,Both UMTS and WLANsWLAN offer higher bandwidth Mobile users accessing the Internet via UMTS/WLAN are free to moveHandover between UMTS and WLANs MIP from IETF provides transparent support for host mobility routing architecture of mobile hostDifficult to maintain the continuity between UMTS and WLAN Point of this article,UMTS/WLAN vertical handover problem,UMTS/WLAN vertical handover support via two types of SCTP single-homing asymmetric configuration dual-homing symmetric configuration Integrated UMTS/WLAN network architecture tightly coupled solutions ：connect UMTS and WLANloose coupling solutions ：separate out UMTS and WLANloose coupling offers several advantages over tight coupling,Overview of Mobile SCTP (1),Originally for VoIP of 3GPPReliabilityMulti-homingestablished over multiple interfaces identified by multiple IP addresses An SCTP association between two hosts, say, A and B, is defined as a set of IP addresses at A + Port-A + a set of IP addresses at B + Port-B.,Overview of Mobile SCTP (2),base version of SCTP cannot be used directly to support UMTS/ WLAN vertical handover Fortunately, the recently proposed DAR extension for SCTP enables the endpoints to add, delete, or change the IP addresses during an active SCTP association using address configuration (ASCONF) messages. basis of mSCTP,Overview of Mobile SCTP (3),mSCTPUsing for supporting UMTS/WLAN vertical handovercapabilities to add, delete, and change the IP addresses dynamically during an active SCTP association,Overview of Mobile SCTP (4),mSCTP Protocol architecture,VERTICAL HANDOVER PROCEDURES (1),FS can also be configured for: Single-homing: The FS provides only one IP address to support handover. Dual-homing: The FS allows more than one (usually two) IP addresses to support Handover procedure has three basic steps: Add IP address Vertical handover triggering Delete IP address,VERTICAL HANDOVER PROCEDURES (2),single-homing configuration,VERTICAL HANDOVER PROCEDURES (3),dual-homing configuration,SIMULATION RESULTS AND DISCUSSIONS (1),use network simulator ns-2 to perform the simulations and obtain set to be 384 kb/s for the UMTS link and 2 Mb/s for the WLAN link delay is set to 100 ms FTP traffic is started at the MC at time 1 s handover triggering process is activated at time 5 s,SIMULATION RESULTS AND DISCUSSIONS (2),simulation results UMTS-to-WLAN handover delay is 533 ms,SIMULATION RESULTS AND DISCUSSIONS (3),simulation resultsWLAN-to-UMTS delay is 513 ms,SIMULATION RESULTS AND DISCUSSIONS (4),throughput performance for vertical handover in both directions,Magazine 2,Interworking techniques and architectures for WLAN 3G integration toward 4G mobile data networks,Note Abstract,WLAN/3G interworking functionINTERWORKING MODEL AND REQUIREMENTSNETWORK SELECTION INTERWORKING SCENARIOS3G-Based Access Control and ChargingREFERENCE POINTSAccess to 3G Packet-Switched ServicesREFERENCE POINTSCONCLUSIONS,WLAN/3G interworking function,WLAN/3G interworking techniques and architectures can supportAuthenticationAuthorizationAccounting WLAN sharingConsistent service provisioning,INTERWORKING MODEL AND REQUIREMENTS (1),high-level WLAN/3G interworking model.,INTERWORKING MODEL AND REQUIREMENTS (2),WLAN/3G interworking mustprovide 3G-based authentication support 802.1X access control support the legacy UAM and open access control schemes,NETWORK SELECTION,MS needs to perform the following selection procedures Select a WLAN that supports interworking with 3G PLMNs MS must select one of the PLMNs several solutions of network selection problem broadcast an SSID with a suitable format transmitting a probe request including a predefined well-known (3G-specific) SSID,INTERWORKING SCENARIOS (1),Scenario 1 Common Billing and Customer CareScenario 2 3G-Based Access Control and Charging Scenario 3 Access to 3G Packet-Switched Services Scenario 4 Access to 3G Packet-Switched-Based Services with Service Continuity Scenario 5 Access to 3G Packet-Switched-Based Services with Seamless Service Continuity Scenario 6 Access to 3G Circuit-Switched-Based Services with Seamless Mobility,INTERWORKING SCENARIOS (1),3G-Based Access Control and Charging (1),INTERWORKING ARCHITECTURE,3G-Based Access Control and Charging (2),AAA SIGNALING,3G-Based Access Control and Charging (3),AAA SIGNALINGMS sends its identity to the WLAN within an EAP-Response/Identity messageMSs identity is NAI-1 usernamerealm WLAN discovers route AAA messages to the 3G PLMN corresponding to this realmAAA access request is sent to the identified 3G PLMN over the Wr interface WLAN sends network advertisement data to the MS use a new EAP method called 3G-Info XML structure,REFERENCE POINTS (1),3G internal interfaces Wr/Wb carries AAA signaling between the WLAN and the 3G / home PLMN in a secure manner Support Radius by acrossWr/Wb Ws/Wc provides the same functionality as Wr/Wb but runs between a 3G AAA proxy and a 3G AAA server,REFERENCE POINTS (2),Wf transport charging information toward the 3G operators CGw/CCF located in the visited or home PLMNWo used by the 3G AAA server to communicate with the 3G OCS,REFERENCE POINTS (3),Wx between the 3G AAA server and the HSS used primarily for accessing the WLAN subscription profiles of the users D/Gr used for exchanging subscription information between the 3G AAA server and the HLR by means of the MAP protocol,Access to 3G Packet-Switched Services (1),INTERWORKING ARCHITECTURE,Access to 3G Packet-Switched Services (2),AAA SIGNALING,Access to 3G Packet-Switched Services (3),AAA SIGNALING,Access to 3G Packet-Switched Services (4),REFERENCE POINTS (1),several additional interfaces Wn used for transporting tunneled user data between the WLAN and the WAG Wm located between the 3G AAA server and PDG used to enable the 3G AAA server to retrieve tunneling attributes and an MSs IP configuration parameters from/via the PDG,REFERENCE POINTS (2),Wi provided via the Wi interface based on IP Wg used by the 3G AAA proxy to deliver routing policy enforcement information to the WAG Wp transports tunneled user data traffic between the WAG and the PDG,CONCLUSIONS,maintain access to the same 3G packet-switched services across several radio access technologies such as IEEE 802.11, HiperLan/2, UTRAN, and GERAN Session mobility is an additional requirement that needs further consideration and presents considerable technical challenges,Magazine 3,IEEE802.11 roaming and authentication in wireless LAN cellular mobile networks,Note Abstract,Integrate wireless LAN serviceIEEE 802.11 WIRELESS LAN ROAMINGRADIUS PROXY IEEE 802.11 HORIZONTAL ROAMINGMOBILE IP HANDOFF PERFORMANCE IMPROVEMENTWIRELESS TRANSMISSION PRIVACYSECURITY ANALYSISAUTHENTICATION AND KEY NEGOTIATION DEMONSTRATIONSUMMARY,Integrate wireless LAN service (1),Integrate wireless LAN service (2),IEEE802.11 service integration functionality integrate into cellular networks Wireless network securityService quality refers to handoff speed and packet loss rate,Integrate wireless LAN service (3),IEEE 802.11 WIRELESS LAN ROAMING (1),IEEE802.11 roaming structure is based on AAA broker with a Remote Authentication Dial-In User Service (RADIUS) server proxy CA servers are special servers that issue and verify certificates to fixed nodes or networks upon request so that they have proofs to identify themselves are organized in a tree topology and working in a distributed way,IEEE 802.11 WIRELESS LAN ROAMING (2),RADIUS PROXY,RADIUS server retrieves remote servers domain from the users request includes the network access identifier identifierdomain_name,IEEE 802.11 HORIZONTAL ROAMING (1),Each network domain is interconnected by AAABs In order to provide IP mobility foreign agent (FA) is placed into the NAS The architecture is able to process two horizontal roaming scenarios The current IEEE802.11 device connects to the network via the NAS Seamless roaming,IEEE 802.11 HORIZONTAL ROAMING (2),IEEE 802.11 HORIZONTAL ROAMING (3),IEEE 802.11 HORIZONTAL ROAMING (4),MOBILE IP HANDOFF PERFORMANCE IMPROVEMENT (1),roam between a wireless LAN and a cellular network routed to the mobile station through its HA HA redirects the data flow to the new IP address For typical data applications is not necessary to use real-time seamless handoff For real-time Internet applications like voice or streaming video ，handoff latency and packet loss performance have become more and more critical,MOBILE IP HANDOFF PERFORMANCE IMPROVEMENT (2),In order to reduce the latency of Mobile IP handoff used to assist Mobile IP handoffpre-registration and authentication data can be sent to the mobile station before it movesAdditional flow control should be taken in the handover perio,WIRELESS TRANSMISSION PRIVACY (1),built-in WEP encryption cannot guarantee data transmission privacy User location updates are transparent to the scheme since user mobility is handled in the network layer FA just relays the authentication message between the mobile station and its home network,WIRELESS TRANSMISSION PRIVACY (2),Authenticating parties share a secret key stored in either the mobile station or its Subscriber Identity Module (SIM) card Authenticating parties do not share a secret key authentication between two mobile stations or a mobile station and a fixed Internet server Visit the Internet public resourc no authentication is needed,WIRELESS TRANSMISSION PRIVACY (3),Authentication and key negotiation protocol between two mobile stations belonging,WIRELESS TRANSMISSION PRIVACY (4),Scheme variation in various authentication scenarios,SECURITY ANALYSIS (1),MS1 finds MS2s home address and creates a nonce with the corresponding hash value HA1 decrypts the message from MS1; HA1 realizes that MS1 i