1. MUSE Winter School 2006 MUSE Winter School BB Europe, Geneva December 11 th, 2006

2. Tutorial Access Architecture 2 MUSE Winter School 2006 Agenda 14:00 Access network architecture (P. Vetter, Alcatel-Lucent) 15:30 Coffee Break 15:45 Optimal resource utilisation by Traffic Engineering (I. Moldován, BUTE) 16:35 Residential Gateway and CPE Configuration and Management (G. Doumenis, ICCS) (*) 17:20 Closing Q&A 17:30 End (*) separate handout

3. MUSE Winter School 2006 MUSE Access Network Architecture Tutorial Peter.Vetter@alcatel.be Francois.Fredricx@alcatel.be MUSE Winter School BB Europe Geneva December 11 th, 2006

4. Tutorial Access Architecture 4 MUSE Winter School 2006 Outline Access Architecture Autoconfiguration Connectivity QoS (List of abbreviations) (References)

5. Tutorial Access Architecture 5 MUSE Winter School 2006 Outline Access Architecture Definitions Business Models Intermezzo: Ethernet Issues with Ethernet in Access Autoconfiguration Connectivity QoS (List of abbreviations) (References)

6. Tutorial Access Architecture 6 MUSE Winter School 2006 Network architecture Definitions (1): Networks RGW Access EN Ethernet aggregation network AN BRAS RGW Service EN Terminals Regional Network Service Network First Mile Customer Premise Networks Aggregation Networks Access Network

7. Tutorial Access Architecture 7 MUSE Winter School 2006 Network architecture Definitions (2): Nodes RGW Access EN Ethernet aggregation network AN BRAS RGW Service EN Terminals Regional Network Service Network First Mile Customer Premise Networks Aggregation Networks Access Network

8. Tutorial Access Architecture 8 MUSE Winter School 2006 Network architecture Definitions (3): Business roles Regional Network Service Network Acce ss Node Acce ss Edge Nod e First Mile Customer Premise Networks Aggregation Networks NAPRNP Connectivity Provider Packager ASP NSP ISP Subscriber Network Access Provider Regional Network Provider Service Providers

9. Tutorial Access Architecture 9 MUSE Winter School 2006 Relations between business roles

10. Tutorial Access Architecture 10 MUSE Winter School 2006 Wholesale - Retail Wholesale means that a provider offers his services to an other provider Retail means that a a provider offers his services directly to the subscriber Unless otherwise specified in this course, these terms mostly apply to a NAP Examples IP wholesale: the NAP does not provide IP connectivity to the subscriber, only L2 connectivity. One or more NSP are responsible to offer IP connectivity. IP retail: NAP is also NSP and offers IP connectivity to subscribers. Application retail: NAP also acts as ASP and offers applications to subscribers.

11. Tutorial Access Architecture 11 MUSE Winter School 2006 Intermezzo: Ethernet Standards IEEE802.3: Physical layer and MAC for LAN (IEEE802.3ah: Ethernet in the first mile) IEEE802.1: 802.1D: Bridging 802.1Q: Virtual Bridged LAN: 12 VLAN ID => 4094 possible (+2 reserved) 802.1P: Use of priority 3 bits in VLAN Tag to differentiate class of service 802.1ad: Provider bridge (Stacked VLANs) 802.1X: Port Authentication PRESFDDASA Length/ Type DataFCS 7 16 6 2 46-1500 4 Bytes PRESFDDASA 7 16 6 S-VLAN tag: 4 C-VLAN tag: 4 2 46-1500 4 Bytes TPID Priority bits VLAN IDCFITPID Priority bits VLAN IDCFI Length/ Type DataFCSPRESFDDASA Length/ Type DataFCS 7 16 6 VLAN tag: 4 Bytes 2 46-1500 4 Bytes TPID Priority bits VLAN IDCFI 16 31 12 bits

12. Tutorial Access Architecture 12 MUSE Winter School 2006 Intermezzo: Ethernet Bridge/Switch Ethernet (CSMA) Bridge Ethernet Bridge (802.1D) (Ethernet Switch) VLAN aware Switch (802.1Q) Hub

13. Tutorial Access Architecture 13 MUSE Winter School 2006 Issues when using Ethernet in Access Ethernet LAN (trusted environment) Ethernet in Access (public network) Bridge learning - Broadcast of some initialisation messages (ARP, DHCP, PPPoE) DOS attacks Confidential info to other users or competing providers Secure and scalable connectivity models Model 1 (L2 forwarding) Model 2 (L3 forwarding) No authentication AAA Configurable MAC@ Conflicts, spoofing Anti-spoofing mechanism No QoS QoS framework

14. Tutorial Access Architecture 14 MUSE Winter School 2006 Outline Access Architecture Autoconfiguration AAA PPP Model Non-PPP autoconfiguration DCHP – 802.1X Connectivity QoS (List of abbreviations) (References)

15. Tutorial Access Architecture 15 MUSE Winter School 2006 Definitions Auto configuration and AAA Autoconfiguration: process of establishing a connection AAA Authentication – process of determining whether someone or something is, in fact, who or what it is declared to be. – based on identifiers and security attributes. – part of an actual access to a network/service in the context of a SLA or contract, and often is linked with a fee (Accounting) Authorization – process of giving individuals access to system objects based on their identity. Accounting – recording, classifying, summarizing, and interpreting of events of a financial character in a significant manner

16. Tutorial Access Architecture 16 MUSE Winter School 2006 Autoconfiguration: PPP model Characteristics : PPP = Point-to-Point Protocol PPP session performs (between CP modem - PPP peer) – Link establishment (LCP packets) – Authentication (optional, PAP or CHAP) – Network-layer protocol (NCP packets : eg IPCP: CP gets its IP@) PPP encapsulation stays during session Origin of PPP for Internet Access via voice band modems (fig.) Continued to be used in DSL PSTN Internet RAS Modem bank

17. Tutorial Access Architecture 17 MUSE Winter School 2006 Autoconfiguration : PPP model PPP in access network PPP can start at : – CPE Modem (router) – Host (PC) PPP can end at : – (IP) DSLAM – BRAS (NAP) – BRAS (NSP) via L2TP tunnel Switch NAPNSP L2TP

18. Tutorial Access Architecture 18 MUSE Winter School 2006 PPPoE PPPoE needed when PPP transported over Ethernet: allows – transport over shared medium – PPP session multiplexing Autoconfig Procedure : - Detection of server(s): PPPoE Active Discovery Initiation (PADI) - Server(s) reply : PPPoE Active Discovery Offer (PADO) - Choice of server : PPPoE Active Discovery Request (PADR) - Server confirmation : PPPoE Active Discovery Session-confirmation (PADS) PPP IP PPPoE 802.3 MAC PPP IP PPPoE 802.3 MAC RFC 2684 AAL5 ATM PPPoEPPPoEoA

19. Tutorial Access Architecture 19 MUSE Winter School 2006 PPPoE initialisation PPPoE Client Ethernet: -DA: Broadcast -SA: User MAC@ PPPoE: -ISP-Name Modem Terminator Access NodeEthernet Switch PPPoE Server in Edge Node Ethernet: -DA: Broadcast -SA: User MAC@ PPPoE: Ethernet: -S-VLAN ID -(C-VLAN ID) -DA: Unicast/Multicast -SA: User MAC@ PPPoE: Ethernet: -S-VLAN ID -(C-VLAN ID) -DA: Unicast/Multicast -SA: User MAC@ PPPoE: Ethernet: -S-VLAN ID -(C-VLAN ID) -DA: User MAC@ -SA: Server MAC@ PPPoE: Ethernet: -S-VLAN ID -(C-VLAN ID) -DA: User MAC@ -SA: Server MAC@ PPPoE: Ethernet: - DA: User MAC@ - SA: Server MAC@ PPPoE: Ethernet: -DA: User MAC@ -SA: Server MAC@ PPPoE: Ethernet: -DA: Server MAC@ -SA: User MAC@ Ethernet: -DA: Server MAC@ -SA: User MAC@ Ethernet: -S-VLAN ID -(C-VLAN ID) -DA: Server MAC@ -SA: User MAC@ Ethernet: -S-VLAN ID -(C-VLAN ID) -DA: Server MAC@ -SA: User MAC@ -ISP-Name - - - - - -

20. Tutorial Access Architecture 20 MUSE Winter School 2006 Non-PPP autoconfiguration PPP is tunnel for each connection Disadvantages of PPP: Separate tunnel per QoS class No support multicast streams Dataplane process Not supported by all types of terminals Non-PPP: => DHCP LCP ? Authentication ? NCP ? DHCP IP 802.3 MAC ConfigData IP 802.3 MAC

21. Tutorial Access Architecture 21 MUSE Winter School 2006 Authentication in Non-PPP model Portal based authentication EAP IEEE 802.1X PANA (Protocol for carrying Authentication for Network Access) DHCP option 90

22. Tutorial Access Architecture 22 MUSE Winter School 2006 Autoconfiguration : DHCP model Characteristics : DHCP = Dynamic Host Configuration Protocol DHCP works in client/server mode DHCP is carried over IP, only during config phase DHCP session (host - server) : – delivers host-specific config parameters – allocates NW addresses to host – automatic : permanent IP@ – dynamic : leased IP@ (limited time) – manual Autoconfig procedure : Discovery of DHCP server(DHCPDISCOVER) Replies of server(s)(DHCPOFFER) Host selects server(DHCPREQUEST) Server acks and sets config(DHCPACK) DHCP IP 802.3 MAC ConfigData IP 802.3 MAC

23. Tutorial Access Architecture 23 MUSE Winter School 2006 IEEE 802.1X 802.1X compliant port of a NAP LAN Uncontrolled Port Port Authentication Entity (PAE) Controlled Port Other Port Services 802.1x Suplicant RADIUS, DIAMETER Authentication Server Port Authorize

24. Tutorial Access Architecture 24 MUSE Winter School 2006 Authentication Architecture

25. Tutorial Access Architecture 25 MUSE Winter School 2006 Autoconfiguration message sequence Autoconfiguration messages

26. Tutorial Access Architecture 26 MUSE Winter School 2006 Exercise (cf. Ethereal read-out) 1.What is the protocol used for autoconfiguration ? 2.Identify the main message groups as explained in the course ? 3.What is the IP-address assigned after autoconfiguration ? 4.What is the IP address of the DNS server ? 5.What is the hexadecimal code for a Broadcast MAC@ ?

27. Tutorial Access Architecture 27 MUSE Winter School 2006 Outline Access Architecture Autoconfiguration Connectivity Model 1: L2 Forwarding Model 2: L3 Forwarding QoS (List of abbreviations) (References)

28. Tutorial Access Architecture 28 MUSE Winter School 2006 Model 1: Ethernet network model CPN NSP/ISP ASP NAP EN Ethernet aggregation network AN CPE EN CPE Ethernet switch (802.1ad) bridged Ethernet switch (S-VLAN aware or 802.1Q) BRAS or Edge Router routed (IPv4/IPv6) IP termination

29. Tutorial Access Architecture 29 MUSE Winter School 2006 Model 1: Cross-connect mode CPN NSP/ISP ASP NAP CPN EN Ethernet aggregation network Routed => L2 termination CPE EN MAC @ FWD within S-VLAN US : L2 termination DS : S-VLAN + C-VLAN tagging S-VLAN 1 S-VLAN 4 S-VLAN 2 S-VLAN 3 C-VLAN 1 C-VLAN 2 C-VLAN-based Cross-connecting : 1(+) C-VLAN(s) 1 line US : S-VLAN tagging DS : S-VLAN stripping IP@ in SubNet service 1 IP@ in SubNet service 2 Bridged => MAC@ FWD

30. Tutorial Access Architecture 30 MUSE Winter School 2006 Model 1: Intelligent bridging mode NSP/ISP ASP NAP CPN EN Ethernet aggregation network AN MAC @ forwarding US : S-VLAN tagging DS : S-VLAN stripping Routed => L2 termination CPE EN MAC @ forwarding within S-VLAN US : L2 termination DS : S-VLAN tagging S-VLAN1 S-VLAN4 S-VLAN2 S-VLAN3 CPN Bridged => MAC@ FWD

31. Tutorial Access Architecture 31 MUSE Winter School 2006 Model 1: Characteristics Intrinsically Based on Ethernet-compliant switches (802.1ad) – MAC learning, VLAN configuration, RSTP, L2 QoS based on p-bits Interpretation of IGMP for multicast tree building Scalability factor; MAC@ (bridging) / stacked VLANs (X-connect) Priority has been put on intelligent bridging – lower complexity, compatible with existing ENs With respect to ATM networks Possibility for cost-effective bandwidth upgrades with Ethernet technology Packet-based nature of Ethernet => – more efficient delivery of multicast or broadcast streams (through the use of multicast trees), – the ability to differentiate QoS on a packet basis for differentiated services, – a simpler provisioning of the network.

32. Tutorial Access Architecture 32 MUSE Winter School 2006 Model 2: IP network model NSP/ISP ASP NAP EN AN CPE EN CPN CPE CPN CPE Ethernet / IP / (MPLS) aggregation network (optional) Ethernet for IPoPPPoE Ethernet switch (S-VLAN aware or 802.1Q) BRAS or Edge Router bridged routed (IPv4/IPv6) IP termination (IPv4/IPv6) Router (IPv4/IPv6) IP for IPoE (IPv4/IPv6)

33. Tutorial Access Architecture 33 MUSE Winter School 2006 Model 2: IP forwarding mode (IPoE traffic) CPN NSP/ISP ASP NAP EN (router) Ethernet aggreg. NW AN CPE EN (BRAS) ARP proxy DHCP relay IP forwarding CPN IP@ in SubNet service 1 (e.g. wholesale) IP@ in SubNet service 2 (e.g. retail) Service connections S-VLANs (1 per EN, + optionally per service)

34. Tutorial Access Architecture 34 MUSE Winter School 2006 Model 2: IP routing mode for retail (IPoE traffic) CPN NSP/ISP ASP NAP EN (router) Ethernet aggreg. NW AN CPE EN (BRAS) CPN DHCP relay IP routing S-VLANs (1 per EN, + optionally per service) IP@ in SubNet retail applications IP@ in private subnet (not globally accessible)

35. Tutorial Access Architecture 35 MUSE Winter School 2006 Model 2: IP routing mode for wholesale (IPoE traffic) CPN NSP/ISP ASP NAP EN (router) Ethernet aggreg. NW AN CPE EN (BRAS) CPN DHCP relay IP routing S-VLANs (1 per EN, + optionally per service) IP@ in SubNet service 1 (e.g. wholesale) IP@ in SubNet service 2 (e.g. retail) IP@ in private subnet (not globally accessible)

36. Tutorial Access Architecture 36 MUSE Winter School 2006 Model 2: Characteristics Intrinsically Higher level of IP-awareness Forwarding decisions based on IP addresses (not necessarily full router) Interpretation of IGMP or PIM for multicast tree building Scalability factor; – ARP tables (IP forwarding) / routing messages (routing case, depending on subnetting) Priority has been put on IP forwarding for IPoE and L2 switching for IPoPPPoE – No need for routing protocols between AN and EN while allowing best subnetting – Easiest migration from existing networks With respect to Ethernet NW model IP as basis for packet handling => – IP QoS – Natural way for peer-peer – Security; separation of user at L2, more control on IP@ by operator than on MAC@ – Scalability; solved for L2, at L3 depends on subnetting scheme – Flexibility for S-VLANs; can be shared over multiple ANs – Future-ready (for service enablers operating at IP level)

37. Tutorial Access Architecture 37 MUSE Winter School 2006 Outline Access Architecture Autoconfiguration Connectivity QoS (List of abbreviations) (References)

38. Tutorial Access Architecture 38 MUSE Winter School 2006 QoS introduction QoS is key in multi-service access End-to-End QoS solutions (e.g. IntServ) commercially failed because of complexity Priority based QoS (e.g. Diffserv) works in Core Networks with sufficient capacity, not suited for Access & Aggregation => Simplified QoS control in Access & Aggregation needed Edge Node Access Node

39. Tutorial Access Architecture 39 MUSE Winter School 2006 Principle of CAC (Call Admission Control) Edge Node Access Node Pre-provisioned pipes RAC Resource Admission Control Function View of flows and BW already allocated Configures policers at borders Admission control after request

40. Tutorial Access Architecture 40 MUSE Winter School 2006 CP QoS Control Functions and Steps RNP Customer ISP ASP1 ASP2 NAP Access EN RGW Terminals AN Ethernet Aggregation network RACF AF S-VLAN RACF for RN S-PDF Policy Enforcement function

41. Tutorial Access Architecture 41 MUSE Winter School 2006 Considerations for CAC CP RNP Customer ISP ASP1 ASP2 NAP Access EN RGW Terminals AN Ethernet Aggregation network RACF AF S-VLAN RACF for RN S-PDF Local RACF Selective CAC: Only for services that need it Only for network sections that need it Centralised or distributed CAC S-VLAN 2 Policy enforcement US: at AN DS: at EN and at AN Per flow or per aggregate

42. Tutorial Access Architecture 42 MUSE Winter School 2006 Standardisation and industry forums relevant for BB Access Architecture DSL Forum Architecture & Transport (e.g. TR-101 Migration to Ethernet in Access) DSL Home (e.g. TR-069 remote management protocol) Operations & Network Service Management Test & Interoperability ETSI-TISPAN NGN Architecture (QoS framework) HGI Requirements for Residential Gateways Other: IEEE802, IETF, MEF, ITU-T

43. Tutorial Access Architecture 43 MUSE Winter School 2006 Agenda 14:00 Access network architecture (P. Vetter, Alcatel-Lucent) 15:30 Coffee Break 15:45 Optimal resource utilisation by Traffic Engineering (I. Moldován, BUTE) 16:35 Residential Gateway and CPE Configuration and Management (G. Doumenis, ICCS) 17:20 Closing Q&A 17:30 End

44. Tutorial Access Architecture 44 MUSE Winter School 2006 Abbreviations (1)

45. Tutorial Access Architecture 45 MUSE Winter School 2006 Abbreviations (2)

46. Tutorial Access Architecture 46 MUSE Winter School 2006 Abbreviations (3)

47. Tutorial Access Architecture 47 MUSE Winter School 2006 Abbreviations (4)

48. Tutorial Access Architecture 48 MUSE Winter School 2006 References