Asymmetric Broadband Roaming over DVB

1. Asymmetric Broadband Roaming over DVB Workshop on Broadband Wireless Ad-Hoc Networks and Services 12th - 13th September 2002 ETSI, Sophia Antipolis, France UNCLASSIFIED R. Segura, NATO C3 Agency, ACT/CISD ramon.segura@nc3a.nato.int UNCLASSIFIED

2. The NATO C3 Agency Role • Perform central planning, systems integration, design, systems engineering, technical support and configuration control for NATO C3 systems and installations • Provide scientific and technical advice and support to the Strategic Commands and other customers on matters pertaining to • operations research, • surveillance, air command and control including theatre missile defence, • electronic warfare and airborne early warning • communications and information systems • Provide technical support for exercises and for unforeseen operations assigned to the NATO Military Authorities (NMA) by the North Atlantic Council (NAC)/Defence Planning Committee (DPC) UNCLASSIFIED

3. The NATO C3 Agency Role (cont.) • Perform technical policy and standardization work in support of the NATO C3 Board (NATO Standardisation Agreements, a.k.a. STANAGs) • Procurement and project implementations The NATO C3 Agency became Member of Project MESA in April 2002 UNCLASSIFIED

4. IP Roaming over DVB: Motivation • Supporting the wideband communications requirements of multi-national forces engaged in rapid coalition deployments, e.g.: • Humanitarian relief • Peacekeeping, Peace Enforcement, Collective defense • Nomadic networks provided by participating nations are integrated into mobile Virtual Network (VN)overlays, subtended by a fixed backbone established by the nation leading the deployment • VNs shall support broadband content delivery from fixed data repositories to hosts in the Mobile Networks through symmetric or asymmetric data transactions • VNs shall support communications between mobile networks • Satellite and Terrestrial DVB bearers, carrying IP over MPEG2 are proposed to transport the forward traffic from fixed to mobile hosts UNCLASSIFIED

5. Mobile Networks, Mobile Routers • Mobile Network: a stubLAN connected to an accessrouter that supports IP mobility as per RFC 2002 (Mobile Router) • A Mobile Router can have multiple roaming interfaces, which can dock into the fixed IP network over different wireless media and access points • The Mobile Router’s counterpart in the fixed network is the Home Agent Router • The Home Agent has WAN access to a number of Foreign Agent routers, which cover the area where Mobile Routers will be roaming during the mission • The Home Agent is the single gateway for all traffic addressed to the Mobile Networks, effectively acting as a registration and routing broker UNCLASSIFIED

6. Mobile Router Principle • The Mobile IP model (RFC 2002) is extended from the classic Mobile Host to the Mobile Router implementation (e.g. Cisco IOS 12.2) • Mobile Routers listen to routing service advertisements from Foreign Agents after entering their coverage area, and can register with the Home Agent through the Foreign Agent of their choice • Following registration, all traffic from fixed and mobile hosts addressed to the Mobile Networks is routed to the Home Agent, and then double-tunneled (using IP-IP encapsulation): • Outer Tunnel: from Home Agent to Foreign Agent • Inner Tunnel: from Home Agent to Mobile Router • All traffic from the Mobile Networks is by default sent to the Foreign Agent, and passed to the destination host using standard routing mechanisms (or mobile IP if the destination host is in a Mobile Network) UNCLASSIFIED

7. Virtual Networks • Objective is to build Virtual Networks in which all nodes are mobile over a wire area of operations • Mobile Routers are access routers in motion around a wide area wireless access infrastructure • Mobile Networks hooked to the Mobile Router need not be Mobile-IP aware, and can maintain their home IP configuration • All traffic is tunneled through a virtual Home Agent down to the Foreign Agent covering the area visited by the Mobile Network • The Home Agent is virtual in the sense that it is not attached to the actual (domestic) home network of any of the mobile networks • The Home Agent advertises IP routes for all registered mobile networks UNCLASSIFIED

8. MN #3.1 MN #4.1 MN #2.1 MN #4.2 MR #3 MR #1 192.182.3.3 MN #2.2 192.182.3.1 MR #2 192.182.3.2 192.182.3.4 MR #4 roaming interfaces Docking Switch (192.182.3.0/24) …at the docking site MN : Mobile Network (LAN) MR : Mobile Router Virtual Networks MN #1.1 UNCLASSIFIED

9. MR #2 Foreign Agent Foreign Agent MR #1 Deployed WAN Home Virtual Network Agent 192.182.3.0/24 Foreign Agent Foreign MR #4 Agent MR #3 IP-IP tunnel Virtual Networks …on the move UNCLASSIFIED

10. Tunnel Overlays • Mobile Routers are logically meshed over a star-shaped overlay of IP-IP tunnels • Hub & spoke topology: spokes are established on-demand, between the Home Agent (hub) and the edge Foreign Agents • IP encryption devices can be used for securing all mobile network traffic, either • as an IPSEC tunnel overlay, i.e. the crypto is placed between the Mobile Router and the Mobile Network(s) => mobile IP protocol goes in the clear - or - • at the air interface edge (*), i.e. the crypto is placed as a bump-in-the-wire between the Foreign Agent and the wireless/broadcast front-end (and between the wireless front-end and the Mobile Router) (*) this configuration requires the IP crypto to support broadcast/multicast UNCLASSIFIED

11. Implementation Constraints • Time, budget and technology constrained military deployment scenarios • establishing a cellular network of several access points with omni directional antennas, full-duplex, wide area coverage and broadband capabilities may not be feasible • Yet traffic flows between fixed and mobile networks are expected to be highly asymmetric in bandwidth, therefore… • broadband unidirectional bearers (e.g. DVB-S / T) could carry forward traffic downstream into the mobile nodes • narrowband channels of opportunity could carry return traffic upstream (mobile IP registration and user traffic) • …take advantage of users in mobile networks already carrying legacy narrowband and personal communications systems, which can be used to hook into the fixed network UNCLASSIFIED

12. Cellular Broadcast Solution • Combine asymmetric split-path network configurations with mobile routing protocols • Connect transmit-only Foreign Agent routers to a star network of broadcast stations blanketing the mission’s target area • Broadcasts from a Foreign Agent can go over a satellite spot beam (DVB-S) or a terrestrial cell (DVB-T) • Mobile Routers will receive the broadcast over one or more wideband roaming interfaces (receive only) • Mobile Router’s return traffic will be diverted over narrowband transmit media, and reach the Foreign Agent over one or multiple hops across the fixed network (first hop being wireless) UNCLASSIFIED

13. DVB-S Scenario • Macro-cellular infrastructure: intent is to provide broadband roaming services to very high-speed moving platforms, e.g. aircrafts, equipped with steerable antennas (phased arrays or reflectors) • Continuous coverage can be provided by multiple downlink spot beams (e.g. at Ka-band), or by multiple satellites • Each footprint is fed by a different Foreign Agent and uplink hub • Mobile units are equipped with satellite tracking antennas, and DVB-S Integrated-Receive-Decoders (IRD) with multiple tuners (one per beam) • Changing beams involves re-registering with the Home Agent through a different Foreign Agent • Registration and return traffic goes over a different medium (e.g. Inmarsat phone, VHF radio, etc.) UNCLASSIFIED

14. DVB-T Scenario • Micro-cellular infrastructure: intent is to provide roaming services to fast moving land platforms equipped with omni-directional antennas • Target area covered by cells of a DVB-T Multi-Frequency Network (MFN) • Each cell is fed by a different Foreign Agent and transmit front-end, and operates at a different channel frequency • Mobile units are equipped with light UHF omni-antennas (GSM-like), and DVB-T IRD, fittedwith multiple tuners (one per MFN channel) • Handovers between cells involve re-registering with the Home Agent through a different Foreign Agent • Registration and return traffic goes over a different medium (e.g. GSM/GPRS, TETRA, 802.11b, UMTS, etc.) UNCLASSIFIED

15. IP over DVB Bearers • Multi-Protocol Encapsulation (MPE, ISO/IEC 13818) to carry unicast and multicast IP packets encapsulated into MPEG2 transport streams • IP/MPEG2 Encapsulator (IPE) placed between the Foreign Agent Router and the DVB modulator (satellite or terrestrial), over Fast Ethernet and MPEG-2 ASI interfaces UNCLASSIFIED

16. The DVB-T Advantage • COFDM over Band IV/V UHF channels (470–872 MHz; 6, 7, and 8 MHz) • NATO can use channels 61 to 69 (790 MHz – 862 MHz), which are part of the military radio relay band (Chester Multinational Coordination Agreeement, 25 July 1997) • Can also use VHF (46-250 MHz) or L-band • COFDM provides • unprecedented performance against fast and selective multipath fading • resilience against narrowband interferers • support of fast moving platforms at data rates up to 10-15 Mbps • DVB-T IRDs are small, compact and inexpensive (e.g. PCMCIA) • DVB-T cells can be very large in open field propagation environments • Use of civilian broadcast infrastructure can significantly shorten the deployment times (i.e. ‘transmittersandbandwidth of opportunity’ ) UNCLASSIFIED

17. Mobile IP - Asymmetric Link support • Asymmetric link support is provided by the latest implementation of RFC 2002 in Cisco IOS (12.2) (*) • Foreign Agent interface can now be a transmit-only Fast Ethernet port • Mobile Router roaming interface is receive-only, return traffic is redirected to a different interface (e.g. a dial-up GSM/GPRS) • One single IP/DVB broadcast bearer can serve multiple Mobile Routers in the cell, each attached to multiple Mobile Networks (stub LANs) • Each Mobile Router roaming interface address is assigned an MPEG2 Program ID (PID). Multicast advertisements’ PID is defined in all receivers • One single Home Agent can manage multiple VN in the area, each with a variable number of “hosts” (Mobile Routers) (*) NC3A tested experimental version in March 2002 UNCLASSIFIED

18. Mobile Router split-path registration over a DVB-T broadcast bearer UNCLASSIFIED

19. Mobile Node: a sample PC-104 stack PC-104 ruggedized enclosure Western Datacom Type-2 IP Crypto (PC-104 form-factor) PCMCIA DVB-T IRD PC-104 embedded PC w. PCMCIA slot Cisco’s Mobile Router prototype, now Cisco 3200 (PC-104 form factor) UNCLASSIFIED

20. Satellite-Terrestrial Augmentation • Motivation: need to receive broadband content from strategic data repositories, as well as from theatre-deployed sources (sensors) • The former is of global interest, and can be transmitted as multicast to all theatres over satellite DVB • The latter is of local interest, and can be transmitted as roaming unicast to a limited area (cell) over terrestrial DVB • Target: mobile units receiving both global and local products aggregated over the same DVB-T broadcast carrier, eliminating the need for a motion-stabilized satellite dish • Means: satellite-terrestrial MPEG2 relay stations, IP/MPEG2 inserters(using opportunistic bandwidth on the received MPEG2 transport stream) • Mobile IP tunnels are combined at MPEG2 level with IP multicast flows received over the satellite channel UNCLASSIFIED

21. Satellite-Terrestrial Relays UNCLASSIFIED

22. … with Mobile Routers UNCLASSIFIED

23. Conclusions • Combining DVB broadcast with mobile routing under very asymmetric networking configurations can speed up deployments involving mobile networks from multiplecoalition partners • Virtual-network topology enables communications among mobile networks through a virtual Home Agent acting as a hub • Proposed architecture is fully based on open standards (ETSI, ISO/IEC, IETF); mainstream, multi-vendor components • COTS technology is combined with MOTS/GOTS Type-1 IP encryption devices to meet military COMSEC requirements • Tradeoff space: symmetric vs. asymmetric broadband access alternatives, in terms of deployment costs, channel capacity, mobility support and coverage range UNCLASSIFIED

24. Questions? UNCLASSIFIED