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Emergency Services and Reliable Service Provisioning in All-IP networks. Dorgham Sisalem Fraunhofer Instituit FOKUS. Outline. Who are we? What have we been doing? All-IP infrastructures: What are our emergency related issues here? Every day life: Provide 911 services Catastrophe:
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Emergency Services and Reliable Service Provisioning in All-IP networks Dorgham Sisalem Fraunhofer Instituit FOKUS
Outline • Who are we? • What have we been doing? • All-IP infrastructures: What are our emergency related issues here? • Every day life: Provide 911 services • Catastrophe: • DoS attacks: Provide secure communication and prevent or at least reduce the effects of DoS attacks • Catastrophe: Make sure that the communication infrastructure is reliable and redundant –allow calls even if your original server has just ceased to exist • Relief services: Provide communication infrastructure for relief workers in ad-hoc networks
FhG-Fokus/Mobis • Fraunhofer: Germany’s national research network • 56 institutes • Tight cooperation with industry • Fokus: research institute for open communication systems in Berlin • 200 People in different competence centers dealing with middle ware, testing, HOT and car technologies and IP communication • IST involvement • Our department ‘mobis’ has been involved in IP telephony since its early beginning
What Have We Done in the Last Years? • Signaling server with open source SIP infrastructure • (thousands of calls per second on an off-shelf PC) • SIP operational experience: We are powering public servers at iptel.org • Long and detailed experience with mobile-IP • Co-authored and standardized firewall-control concept in IETF (MidCom, RFC3303) • Testing suites (TTCN-3) for robust products developed • QoS work: FEC algorithms, packet loss concealment • RTP created in Fokus
All-IP Multimedia Services: Where are we and what are the problems? • “basic package” up and running • Signaling standardized and deployed for few years now • Media quality mostly sufficient • Service integration happens: Instant messaging, web, VoIP • Current problems: • How to provide 911 services? • How to provide reliable services under emergency or attack situations? • How to provide communication services in catastrophe situations?
Requirements for Emergency Services in All-IP Environments • Horizontal and vertical location identification accuracy • Finding user location • Determining the appropriate PSAP • Sending user location data to PSAP • Addressing • How to signal an emergency in a roaming situation? • Reliability and QoS support: • QoS Architecture: How to provide QoS guarantees for emergency calls • Social: How to asses and prove urgency • QoS: How to enforce priorities across a complex systems (IP, signaling, gateways, …) along an uncontrolled end-2-end path • Capacity engineering: How to deal with mass urgency needs?
Reliable and Safe Service Provisioning: Problems • First line of defense against any kind of attack or event is solid and reliable service infrastructure • Multimedia services depend on a large row of components: • End devices: • Software and hardware failures • Network: • Routers, physical links • Supporting services • DNS, proxies, firewall, NAT, AAA servers • Any of these components can fail due to internal problems or DoS attacks.
Why I Do Not Want to Rely on My SIP Phone in Emergency Today • Age • Software still young (~ 5 years, cf. tens of years in PSTN) and buggy • Conceptual Gaps • Availability of open communication systems lower – they are exposed to bogus implementations and attacks • Bogus implementations account for 50% of total resource consumption! • Concepts for network reliability not mature yet • Bandwidth sharing may kill any communication attempt
To-Do List: Reliability • Objective: To keep infrastructure responsive under server, host and network failures • Issues: • Complexity: an IP telephony network depends on many components, all of which may fail: IP routing, DNS, firewalls, call signaling • Latency: in a lossy environment, it is difficult to detect failure in real-time • Failures can have broad impact. Tandem redundancy not good enough in open networks
To-Do-List: Robustness • Objective: To remain responsive under heavy stress caused by exceptional circumstances or security attacks • Issues: • Conflicting requirements: • Good security to preserve resource wasting by unathorized users • We want anyone, even non-authenticated users, to participate in emergency calls • Surviving denial of service attacks not easy • Identifying DoS attacks not easy • Devise solutions and mechanisms for reducing effects of DoS • Operational dependency on systems such as DNS
Reliable and Safe Service Provisioning: Goals • Research large-scale robustness, which follows the IP model with no single point of failure. • Distribute signaling services across a large number of cooperating systems whose aggregated capacity can easily cope with large-scale failures and attacks • It is even thinkable for end-devices to participate in the federations • Reality check: Can end-devices bear the load? • Yes! We’ve architected server which even on IPAQ with 802.11 make 300 calls per second. • Achieve secure access to services such as IP-Telephony and still maintain the open system architecture • Allow only eligible users to use the service but allow also everybody to use the service in case of emergencies
Service Provisioning in Ad-Hoc environments • Support a communication infrastructure in catastrophe locations • Research in ad-hoc networks is mostly dedicated to optimizing routing • However, communication services require • Distributed services such as name translation (SIP address to IP address) • Cooperation between devices with different network technologies (Bluetooth and IEEE 802.1b) • Dynamic establishment of service providers • Example: mobile ad-hoc networks in which each phone is able to serve as PBX and help other systems to establish communication with each other • Issues of trust, service location and mobility to be considered here
Where are we now? • Open source SIP infrastructure released • Proxy, registrar, redirect • AAA, SNMP, Radius support • Application server and configuration utilities • Available from www.iptel.org • Active work in the area of automatic failure detection of SIP servers and removal • First ideas implemented in our SIP platform • Work on DoS attacks on SIP infrastructure • What types are there and how to prevent them? • Work on QoS reservation and policing mechanisms • iptel.org is used demonstrate reliability concepts and mechanisms for DoS prevention