© nokiaiprout98.ppt / 04.10.1998 / mha page: 1 routers and router markets mika hatanpää 1998...

© NOKIA IPROUT98.ppt / 04.10.1998 / Mha page: 1

Routers and Router MarketsRouters and Router MarketsMika HatanpääMika Hatanpää

19981998

Overview of routing and routers

Router classification

Router vendors

Router markets

Router products

Some parts of this material is are for Nokia internal use only!!!


Levels of analysis in this presentationLevels of analysis in this presentation

Principles, Requirements

Protocols

Specifications, RFCs, draft specs• Routers according to RFC's

Products• Some examples and test results

Markets• Vendors and market situation


Layers of the TCP/IP stackLayers of the TCP/IP stack- Hosts and routers -- Hosts and routers -

Application

TCP/UDP

IP

Network 1

IP

Application

TCP/UDP

IP

Network 2

Host 1 Router Host 2

Data LinkData Link Data Link

Routing

TCP/UDP

The coloured areas of the router box are the most interesting

ones in this presentation


Routing and routers (1/5)Routing and routers (1/5)

• Routing is a process that routes traffic from source to destination according to addresses, quality requirements, and constraints set by the network

• Routers are devices that perform the network layer (layer 3) forwarding function of the Internet protocol suite.

• The Internet community usually refers to such devices as IP routers or simply routers.

• An IP router can be distinguished from other sorts of packet switching devices in that a router examines the IP protocol header as part of the switching process.

• It generally removes the Link Layer header a message was received with, modifies the IP header, and replaces the Link Layer header for retransmission.

• There exists also devices that do packet switching on the link layer (layer 2) but these devices are usually called bridges or switches.

• However, the differences between routers and switches are becoming more and more fuzzy



• Historically, routers have been realized with packet-switching software executing on a general-purpose CPU.

• As custom hardware development becomes cheaper (ASICs) and as higher throughput is required, special purpose hardware is becoming increasingly common!

• A router connects to two or more logical interfaces, represented by IP subnets or unnumbered point to point lines.

• it has at least one physical interface (usually at least 2)

• Forwarding requires the router to choose the address and relevant interface of the next-hop router or (for the final hop) the destination host.

• Forwarding depends upon a route database (routing table) within the router.

• The routing database should be maintained dynamically to reflect the current topology of the Internet system

• A router accomplishes this by participating in distributed routing and reachability algorithms with other routers (routing protocols)

• Routers provide datagram transport only, and they seek to minimize the state information necessary in the interest of routing flexibility and robustness.



A characteristic router performs the following functions:

1. Conforms to specific Internet protocols including the Internet Protocol (IP), Internet Control Message Protocol (ICMP), and others as necessary (routing protocols)

2. Interfaces to two or more packet networks. For each connected network the router must implement the functions required by that network. These functions typically include:

• encapsulating and decapsulating the IP datagrams with the connected network framing (e.g., an Ethernet header and checksum)

• sending and receiving IP datagrams up to the maximum size supported by that network, this size is the network's Maximum Transmission Unit or MTU

• translating the IP destination address into an appropriate network-level address for the connected network (e.g., an Ethernet hardware address), if needed

• responding to network flow control and error indications, if any.



3. Receives and forwards Internet datagrams. Important issues in this process are buffer management, congestion control, and fairness

• Recognizes error conditions and generates ICMP error and information messages as required.

• Drops datagrams whose time-to-live fields have reached zero.

• Fragments datagrams when necessary to fit into the MTU of the next network.

4. Chooses a next-hop destination for each IP datagram, based on the information in it's routing database.

5. Supports an interior gateway protocol (IGP) to carry out distributed routing and reachability algorithms with the other routers in the same autonomous system.

• In addition, some routers will need to support an exterior gateway protocol (EGP) to exchange topological information with other autonomous systems.

6. Provides network management and system support facilities, including loading, debugging, status reporting, exception reporting and control.



• General requirements for routers:

• Advanced Routing and Forwarding Algorithms

• highly dynamic, minimal overhead, …

• High Availability

• always working, instant recovery, robusticity, …

• Advanced O&M Features

• normal operation should not require O&M, remote operation

• monitoring, diagnostics, statistics, …

• High Performance

• the lines are currently full...


Router requirements (1/10)Router requirements (1/10) - Link layer requirements - - Link layer requirements -

• Routers have essentially the same Link Layer protocol requirements asother sorts of Internet systems

• The information that must pass from the Link Layer to the Internetwork Layer for each received packet is:

• The IP packet

• The length of the data portion (i.e., not including the Link-Layer framing) of the Link Layer frame

• The identity of the physical interface from which the IP packet was received

• The classification of the packet's destination physical address as a Link Layer unicast, broadcast, or multicast

• Also the source physical address should be provided


Router requirements (2/10)Router requirements (2/10)- Link layer requirements -- Link layer requirements -

• The information that must pass from the Internetwork Layer to the Link Layer for each transmitted packet is:

• The IP packet

• The length of the IP packet

• The destination physical interface

• The next hop IP address

• Also the Link Layer priority value should be provided

• The Link Layer must notify the Internetwork Layer if the packet to be transmitted causes a Link Layer precedence-related error

• Routers that have point to point general purpose serial interfaces must implement PPP


Router requirements (3/10)Router requirements (3/10)- Internet layer protocols -- Internet layer protocols -

• Routers must implement IP and ICMP protocols

• There are many optional features however

• IGMP should be implemented as well

• A router must support fragmentation and reassembly

• A router must implement mandatory IP extensions:

• subnets

• IP broadcast

• Classless Inter-Domain Routing (CIDR)


Router requirements (4/10)Router requirements (4/10)- Forwarding algorithm -- Forwarding algorithm -

1. The router receives the IP packet from the Link Layer.

2. The router validates the IP header.

• Note that IP reassembly is not done, except on IP fragments to be queued for local delivery in step (4)

3. The router performs most of the processing of any IP options.

• some IP options require additional processing after the routing decision has been made.

4. The router examines the destination IP address to determine how it should continue to process the IP datagram. There are three possibilities:

• The IP datagram is destined for the router, and should be queued for local delivery, doing reassembly if needed

• The IP datagram is not destined for the router, and should be queued for forwarding

• The IP datagram should be queued for forwarding, but (a copy) must also be queued for local delivery

• The next steps are diferent for unicast and multicast!


Router requirements (5/10)Router requirements (5/10)- Forwarding algorithm for unicast -- Forwarding algorithm for unicast -

5. The forwarder determines the next hop IP address for the packet, usually by looking up the packet's destination in the router's routing table.

• This procedure also decides which network interface should be used to send the packet.

6. The forwarder verifies that forwarding the packet is permitted.

• The source and destination addresses should be valid

• If the router supports administrative constraints (like firewalls) on forwarding, those constraints must be satisfied.

7. The forwarder decrements (by at least one) and checks the packet's TTL

8. The forwarder performs any IP option processing that could not be completed in step 3.

9. The forwarder performs any necessary IP fragmentation

• Since this step occurs after outbound interface selection (step 5), all fragments of the same datagram will be transmitted out the same interface.


Router requirements (6/10)Router requirements (6/10)- Forwarding algorithm for unicast -- Forwarding algorithm for unicast -

10. The forwarder determines the Link Layer address of the packet's next hop.

• The mechanisms for doing this are Link Layer-dependent

11. The forwarder encapsulates the IP datagram for the link layer

• an appropriate Link Layer frame is used

• The link layer frames are queued for output on the interface selected in step 5.

12. The forwarder sends an ICMP redirect if necessary

• The ICMp redirect tells a local host to use different next hop router

• The forwarding algorithm is slightly different for multicast and there exists an extensive amount of other rules for the forwarding process...


Router requirements (7/10)Router requirements (7/10)- Transport layer -- Transport layer -

• A router is not required to implement the transport layer protocols

• But the application protocols (like routing protocols) usually require both TCP and UDP to be present


Router requirements (8/10)Router requirements (8/10)- Application layer, Routing protocols -- Application layer, Routing protocols -

• The most important application layer protocols are the routing protocols for Interior and Exterior routing

• Requirements for interior routing protocols (IGP) are:

• Respond quickly to changes in the internal topology of an AS

• Provide a mechanism such that circuit flapping does not cause continuous routing updates

• Provide quick convergence to loop-free routing

• Utilize minimal bandwidth

• Provide equal cost routes to enable load-splitting

• Provide a means for authentication of routing updates

• A router that implements any routing protocol other than static routing must implement OSPF !!!

• A router that implements any exterior routing protocol must implement BGP !!!


Router requirements (9/10)Router requirements (9/10)- Application layer, Management protocols -- Application layer, Management protocols -

• Routers must be manageable by SNMP

• Standard MIBs for routing protocols must be used

• Vendor specific MIBs can be used

• No other MUST requirements

• BOOTP could be used for bootloading and configuting...


Router requirements (10/10)Router requirements (10/10)- O&M -- O&M -

• Router O&M includes the following kinds of activities:

• Diagnosing hardware problems in the router's processor, in its network interfaces, or in its connected networks, modems, or communication lines.

• Installing new hardware

• Installing new software

• Restarting or rebooting the router after a crash

• Configuring or reconfiguring the router (a router must provide out-of-band access in addition to the in-band access)

• Detecting and diagnosing Internet problems such as congestion, routing loops, bad IP addresses, black holes, packet avalanches, and misbehaved hosts.

• Changing network topology, either temporarily (e.g., to bypass a communication line problem) or permanently.

• Monitoring the status and performance of the routers and the connected networks.

• Collecting traffic statistics for use in (Inter-)network planning.

• Coordinating the above activities with appropriate vendors and telecommunications specialists.


Router classification (1/2)Router classification (1/2)

• Personal routers (PR)

• routers targeted for individual users or very small offices

• typically from 1 to 10 IP addresses

• WAN interfaces: asynchronous, serial, and integrated services digital network (ISDN)

• list prices are from U.S.$500 to U.S.$1,500

• Branch office routers (BOR)

• routers used to link remote LANs to a corporate network (not access servers)

• serial, leased-line interfaces or frame relay interfaces and may have dial backup

• they are multiprotocol

• Midrange routers (MRR)

• routers typically configured with up to 24 LAN and 24 WAN ports

• incorporate multiple media, such as Ethernet and token ring, Fast Ethernet, FDDI, and ATM.

• Examples: Cisco Systems Inc.'s 4000 series, 3Com Corporation's NETBuilder II, and Bay Networks Inc.'s LN family.


Router classification (2/2)Router classification (2/2)

• High-end routers (HER)

• routers typically configured with a minimum of 24 LAN and 24 WAN ports

• incorporate multiple media, such as Ethernet, Fast Ethernet, token ring, FDDI, and ATM

• fault tolerance suported: dual power supplies, hot swappable cards, redundant buses, …

• Examples: Cisco's 7500 and Bay's BN family

• Multigigabit routers (MGBR)

• routers capable of providing multigigabit bandwidth in support of high-speed WAN interfaces.

• typically designed for the Internet Core and support only the IP protocol suite

• media types include ATM (OC-3, OC,-12, and OC-48), IP over SONET, high-speed serial interface (HSSI), and in the future wave-division multiplexing (WDM)

• fault tolerance supported: dual power supplies, hot swappable cards, and redundant buses.

• Examples: Cisco's 12000 (GSR) and Ascend's GRF family


Typical IP network architectureTypical IP network architecture

SWITCH/ROUTER

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EDGE ROUTER

Internet(HER, MGBR)

ACCESS ROUTER

ACCESS SERVER

PSTN/ISDN, (PR)ADSL

GSM

(BOR,MRR)

(MRR, HER, MGBR)


Router vendors - Cisco (1/2)Router vendors - Cisco (1/2)

• Cisco Systems is the worldwide leader in networking for the Internet

• Cisco has three lines of business:

• Enterprises - Large organization with complex networking needs. Enterprise customers include corporations, government agencies, utilities and educational institutions.

• Service Providers (ISPs) - Companies that provide information services, including telecommunication carriers, Internet Service Providers, cable companies, and wireless communication providers.

• Small/Medium Business – Companies with a need for data networks of their own, as well as connection to the Internet and/or to business partners.

• Cisco sells its products in approximately 115 countries

• Cisco has grown very fast by doing acquisitions

• Cisco has formed alliances with Telcos

• Cisco sells

• Routers (like 7000 and 12000 series)

• LAN Switches (Catalyst products)

• ATM Switches, WAN Switches, Firewalls, …


Router vendors - Cisco (2/2)Router vendors - Cisco (2/2)

• Financial facts:

1997 1996 1995 1994 1993

Net sales $6,440 $4,096 $2,232 $1,334 $714

Net income $1,048 $913 $456 $332 $176

Net income per share 1,52 1,37 0,72 0,54 0,30

Total assets $5,451 $3,630 $1,991 $1,129 $656

• Cisco employs approximately 15,600 worldwide

• about 8,000 in the San Francisco Bay Area

• Cisco's market shares in some key areas (1Q98):

• Routers: 63%

• LAN Switches: 45%

• ATM WAN Switches: 31%

• ATM LAN Switches: 21%

• Remote access: 26%


Router vendors - Bay NetworksRouter vendors - Bay Networks• Bay Networks is one of the big datacom companies

• Bay Networks has more than 7,000 employees operating in 90 countries

• Key figures:1997 1996 1995

Net sales $2,093 $2,057 $1,404

Net income (loss) per share $(1.46) $1.04 $0.69

• Bay networks is currently a Nortel Networks Business!

• Like Cisco Bay has also done many strategic acquisitions

• Bay networks sells:

• Remote access concentrators and servers

• Backbone routers (Accelar gigabit router)

• Cable modems, Access Nodes (BayStack)

• ATM Switches (Centillion)

• LAN Switches, HUBs

• Bay has about < 20% market share in LAN Switches and ATM LAN Switches

• New products like cable modems and Accelar Switches seem quite promising...


Router Vendors - AscendRouter Vendors - Ascend

• Ascend has grown very fast by making strategic acquisitions


1997 1996 1995 1994 1993

Net Sales $1,167 $890 $287 $89 $23

Net income (loss) ($124) $183 $52 $15 ($2)

Net income (loss) per share ($1) $1 $0 $0 ($0)

Total Assets $1,137 $922 $481 $126 $31

• Ascend Communications, Inc. was founded in 1989

• Ascend products are

• Edge layer products like xDSL modems

• Access layer products like access concentrators (Ascend has quite big market share here)

• Core layer products like the new GRF gigabit router and ATM WAN Switches

• Ascend has not got LAN products

• Ascend has about 1700 employees


Router vendors - 3ComRouter vendors - 3Com• 3Com is one of the biggest datacom companies but routers do not play a key

role in it's product portfolio


• 3Com's product mix includes for example:

• Network interface cards

• High-speed modems (analog, ISDN, cable and DSL)

• Hubs, Switches

• Routers

• Internet access devices, Remote access equipment

• 3Com has approximately 13,000 employees worldwide

• 3Com acquired US Robotics last year

1997 1996 1995

Net Sales $3,147 $2,327 $1,593

Net income $373 $177 $144

Total assets $2,266 $1,525 N/A


Router vendors - NokiaRouter vendors - Nokia

• Nokia is not a big router vendor

• The only true Nokia Routers are the ones developed by IPRG

• IP400 Series

• Nokia's financial figures for comparision (1 USD = 5 FIM in calculations):

1997 1996

Net sales $10,522 $7,864

Operating profit $1,691 $853

Net profit $1,252 $653

Earnings per share $4,23 $2,35


Router markets (1/4)Router markets (1/4)For internal use only !

The contents of this slide are for Nokia employees only.

If you are such a person ask for another copy of this slide

set from [email protected]


Router products - Cisco 7513 (1/3)Router products - Cisco 7513 (1/3)

• Supported network interfaces:

• Ethernet 10BaseT, AUI1, and 10BaseFL

• Fast Ethernet (100BaseT and MII)

• Token Ring

• FDDI (half and full duplex)

• HSSI

• Synchronous serial

• ATM

• Multichannel on T1 or E1 lines, ISDN PRI

• Channelized T3

• Packet OC-3

• IBM channel

• Power supplies: 2

• Interface processor slots: 11



• Route Switch Processor module (2 slots)

• Processor type: MIPS RISC 100-200 MHz

• 32-MB DRAM default, upgradeable to 128 MB

• 16-MB Flash memory via PCMCIA Flash memory cards, upgradeable to 40 MB

• Battery backup

• Real-time calendar clock

• Dimensions (H x W x D): 85.73 x 44.45 x 55.88 cm

• Weight: Chassis with blower module, 2 power supplies and all slots filled: 72.58 kg

• Software options:

• IP Routing Protocols: RIP, OSPF, BGP-4, IGRP, ….

• IP Multicast Protocols: DVMRP, IGMP, ...

• IP Router Functionality: IP, UDP, TCP, ICMP, ARP, CIDR, BOOTP, DHCP, TFTP, PPP, SLIP, Telnet, Finger, RARP, TACACS, SNMP, …

• Link layer support for all possible interface types …



• Capacity is highly dependent of the media type used and the configuration of the router

• Cisco 7513 equiped with 200MHz MIPS RISC CPU, VIP Distributed Optimum Switching modules, and Full Duplex Fast Ethernet Cards routes over 1M packets per second when using 64 byte IP packets.


Router products - Nokia IP400 (1/4)Router products - Nokia IP400 (1/4)

• Nokia Software Specifications of IP400

• IP Routing Protocols: RIP, OSPF, IGRP, BGP-4, Route redistribution,

• IP Multicast Protocols: DVMRP, IGMP

• IP Router Functionality: IP, ICMP, ARP, Router discovery, CIDR, BOOTP, DHCP, Relay agent, ...

• Redundancy: Virtual Router Redundancy Protocol

• Checkpoint Firewall

• Interfaces supported by SW:

• Ethernet/Fast Ethernet

• Fiber Distributed Data Interface (FDDI)

• Asynchronous Transfer Mode (ATM)

• Frame Relay (available early 1998)

• Point-to-Point Protocol

• Cisco HDLC


Router products - Nokia IP400 (2/4)Router products - Nokia IP400 (2/4)• Network Management

• Command line via Telnet

• Software and Configuration via File Transfer Protocol (FTP)

• Simple Network Management Protocol (SNMP), basic MIBs

• Voyager Web tool via HyperText Transfer Protocol (HTTP)

• Nokia Hardware Specifications IP440

• PentiumPro processor

• Interfaces

• ATM

155 Mbps SONET/SDH STS3c/STM1 RJ45 Connector

Unshielded Twisted Pair

155 Mbps SONET/SDH STS3c/STM1 SC Connector

Multimode Fiber

• Ethernet/Fast Ethernet

IEEE 802.3 10BASE-T, 100BASE-TX RJ45 Connector

Unshielded Twisted Pair

Half- or Full-Duplex


Router products - Nokia IP400 (3/4)Router products - Nokia IP400 (3/4)

• … Interfaces

• FDDI

ISO9314/ANSI X3T9.5 SC Connectors

Multimode Fiber

Dual Attachment Station

• Synchronous Serial

T1/E1 synchronous serial ITU-T V.35, X.21

Clocking to 2.048 Mbps

• Physical size

• 19-inch Rack Mountable

• Dimensions: HxDxW 18 x 46 x 43 cm

• Weight 42 lbs (19 kg)

without interfaces


Ipsilon routing kernel SW architecture (4/4)Ipsilon routing kernel SW architecture (4/4)- Outdated information -- Outdated information -

For internal use only !





Routing protocols etc. (1/2)Routing protocols etc. (1/2)

• Routing Information Protocol (RIP, RFC 1058)

• The simplest IP routing protocol, RIP is ideal for straightforward network topologies. Workstations also use RIP to send their traffic along an optimal, reliable path.

• Open Shortest Path First (OSPF, RFC 1247)

• A more advanced IP routing protocol, OSPF uses a link-state algorithm for faster convergence around failures. Support for variable-length subnet masks (CIDR) makes it particularly useful in networks where IP addresses must be conserved.

• Interior Gateway Routing Protocol (IGRP)

• Not an IETF standard, but commonly used with equipment from Cisco Systems, IGRP's fine-grained metrics make it particularly useful in networks with mixed-speed links, such as those supporting both FDDI and Ethernet in parallel.

• Border Gateway Protocol (BGP, RFC 1654)

• BGP is a highly sophisticated IP routing protocol mostly used by ISPs. Support for detailed policy controls make it particularly useful between administrative domains.

• Static Routing

• Support for static routes allows the network designer to use manual intervention to override routing protocols.


Routing protocols etc. (2/2)Routing protocols etc. (2/2)

• Redistributed Routing

• Support for redistributed routes allows the network designer to propagate routes learned from one protocol into other protocols. For example, backbone routes learned via OSPF can be redistributed to workstations via RIP. As another example, routes learned from Cisco equipment via IGRP can be redistributed to standards-based equipment via OSPF. Filters allow network designers to propagate route information selectively, enhancing network security.

• Scalable IP Multicast

• The purpose of IP multicast protocols is to deliver a stream of IP packets to multiple destinations quickly and efficiently.

• Distance Vector Multicast Routing Protocol (DVMRP, RFC 1075)

• This specialized IP routing protocol complements the unicast protocols described above to create a logical tree along the most efficient path between the source and all destinations. DVMRP is widely used in the MBONE, a large-scale multicast overlay across the Internet.

• Internet Group Membership Protocol (IGMP, RFC 1112)

• Used with DVMRP, this protocol allows applications and hosts to indicate which IP multicast packets they wish to receive.


The relative advantages of bridging and routingThe relative advantages of bridging and routing

• Advantages of Bridging

• Provides simpler installation and configuration

• Automatically locates users via 'self-learning' capabilities

• Handles all protocols

• Provides more flexibility

• Protects investment as needs change

• Does not require software upgrades for new releases of each protocol

• Uses automatic path optimisation

• IEEE 802.1 standard spanning Tree Protocol

• One path control algorithm for all protocols

• Provides automatic re-routing

• Results in lower cost of ownership

• Fewer staff needed

• Fewer software upgrades required

• Advantages of Routing

• Provides simpler administration of network security

• Helps comply with TCP/IP address restrictions if using the Internet Network

• Uses WAN links more efficiently because they do not carry LAN framing overhead

• Isolates broadcast traffic to individual LANs

• May reduce total overhead

• Useful for lower-speed WAN links

• Complements bridging in large networks

• http://www.ktgroup.co.uk/techinfo/abtbridges.html

© nokiaiprout98.ppt / 04.10.1998 / mha page: 1 routers and router markets mika hatanpää 1998...

Documents

ip routers

network routers

router box

characteristic router

routing database

overview of routing

ip header

distributed routing