isp 를 위한 초고속망 구축 기술

[email protected] ISP를 위한 초고속망 구축기술 1

ISP 를 위한 초고속망 구축 기술

장우현[email protected]

데이콤 EC 인터넷사업본부 보라넷팀


Topics

• LAN

• WAN

• Server System

• Traffic Caching* Access Network (home-to-ISP), Monitoring, Accounting 은

다루지 않았음


LAN parts

• Bandwidth 의 변화– Shared 10Mbps– Switched 10Mbps– Shared 100Mbps– Switched 100Mbps– Switched 2Nx100Mbps– Switched 1Gbps– Shared N x Gbps


BORANet Router Port 의 Bandwidth Usage 변화

Bandwidth of a Router port

0

100

200

300

400

500

600

94 95 96 97 98 99

Year

Mb

ps


High Speed LAN Solutions

• 100Mbps FDDI

• 100Mbps FastEthernet

• ATM LAN Emulation

• FastEtherChannelFastEtherChannel– 2^N x FastEthernet

• Gigabit Ethernet InterfaceGigabit Ethernet Interface

• IP Ring (Gigabit)IP Ring (Gigabit)


FastEtherChannel

• 2^N x FastEthernet (N = 1,2,3)– Router <-> Switch– Switch <-> Switch– Logical One Interface– 여러업체에서 지원

• MAE-WEST, PAIX, DACOM BORANetMAE-WEST, PAIX, DACOM BORANet 등에서 이용

800M 400M200M


Gigabit Ethernet Interface

• Most of the famous vendors are providing the Gigabit Interface– ‘98 년중부터 출시됨– Cisco, 3Com, ....– Alteon, Foundry, ...

• FastEtherChannel 보다 성능 , 확장성 , 비용면에서 유리 – FasEtherChannel 은 Gigabit Interface 로 가기

위한 Interim Solution– 가능하다면 100M Interface 에서 Gigabit InterfacGigabit Interfac

ee 로 바로 전이하는 것이 바람직로 바로 전이하는 것이 바람직


IP Ring• Shared Gigabit Ring• (Wide AreaWide Area) Local Area Network

– Same Network Address• based on SONET/SDH• FDDI 100Mbps 한계를 벗어남 • IP Ring will come to us Soon!

서울 수원

안양

Gigabit Ringbased on SONET/SDH

10.0.0.1 10.0.0.3

10.0.0.2


WAN Parts

• Bandwidth 의 변화– 9.6/56/64Kbps– Fractional T1/E1– T1/E1– T3– OC3/STM1 (155M)– OC12/STM4 (620M)– OC48/STM16 (2.48G)


DACOM <-> KT 간 Bandwidth 변화

Bandwidth between DACOM and KT

0

50

100

150

200

250

300

94 95 96 97 98 99Year

Mb

ps


High Speed WAN Solutions

• ATM

• Packet Over SONET/SDH


POS (Packet Over SONET/SDH)

• A high-speed WAN transport that leaves LAN traffic in its native formatnative format

• Packet-Over-SONET/SDH is the serial transmission of data over SONET frames through the use of Point-to-Point Protocol (PPP)– RFC 1619, PPP over SONET/SDH– RFC 1662, PPP in HDLC-like Framing


Benefit of POS

• High utilization of WAN bandwidth– Packet over SONET provides 98% utilization98% utilization

EtherEtherSizeSize

(Byte)(Byte)

SPESPEEff.Eff.%%

SPESPEEff.Eff.%%

POSPOS ATMATM

6464

128128

256256

512512

10241024

15181518

20482048

43524352

44884488

86.886.8

9494

9797

98.698.6

99.399.3

99.599.5

99.699.6

99.899.8

99.899.8

4343

6969

7575

8585

8686

8888

8989

8989

8989


Which One? POS or ATM

• Consider IP over SONET/SDH when business model or majority of traffic is IP CentricIP Centric

• Consider ATM for aggregation of multiple servicesmultiple services on a common transmission infrastructure


BORANet Backbone

• T3 now

• We are considering the POS for the national and int’l backbone

• DACOM BORANet <-> KT KORNET – T3 x 3 now-> POS

1 x STM1STM12 x STM11 x STM4


Server System Parts

• One Big Machine: No way– Use Multiple MachineMultiple Machine– to serve the large and bursty traffic

• Server RackServer Rack

DNS Servers Web ServersVideo Servers


Share the Disk Storage• Dedicated NFS Server SystemDedicated NFS Server System 이용

– Hot Swappable Disk without Setup– High Speed I/O Operations– Multiple Fast Interfaces


Server Load 분산

• DNS Round-Robin 이용한 load 분산

• Layer 4 SwitchLayer 4 Switch 이용한 load 분산– Application port number 를 보고 분산시킴– DNS, Web, Telnet, FTP, NNTP, etc.

ip: 10.0.0.1port: 23

10.0.0.2session 10 개

10.0.0.3session 10 개

10.0.0.4session 9 개Layer 2 Switch

Layer 4 Switch


Off-the-Topic

• Don’t consider only SUN, HP, DEC, ....– They are expensive.

• We can buy the systems having same performance and quality with SUN, HP, DEC at half-price


Traffic Caching

• Web Traffic Caching– save the cost for WAN connection– improve the performance at the user-view– upto 50% hit ratio– Most of Korea ISPs are caching the traffic to sav

e the int’l circuit– 투자비를 2~3 개월안에 회수 가능

• DNS Request Caching– improve the response time


Traffic Caching (cont.)

• Many ISPs in the world are installing the cache-farms at their POPs.

SanFrancsico New York

Dallas

cache-farm

cache-farm

cache-farm


Traffic Caching (cont.)

• Web Caching Servers– Inktomi, Netcache, Cisco Cache, CacheFlow, ...

• L4 Switches– Alteon, Foundry, RAD, ...– Gigabit Interface 지원– Layer2 Switch 로 기능으로도 뛰어남


Challenges of IP Network

• Accounting

• Class of Services

• Quality of Services

• High-Speed Switching

• VPN provided by the service provider’s network

isp 를 위한 초고속망 구축 기술

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