Network Services. Geoff HUSTON

Transcription

1 Network Services Geoff HUSTON

2 IP Access is not enough An ISP service also requires: mail & mailing lists DNS web usenet ftp...

3 Mail Services Outgoing Mail server Outbound Mail Outbound Mail POP or IMAP Access to Mail Account Mail Client Inbound Mail delivery Mail Mail Alias Local Access Account Backup Secondary Mail

4 Mail Services Customer mailboxes SMTP server POP / IMAP access server account management alias management

5 Mail Services SMTP relay for outbound mail Secondary MX for customers Mail List management for customers

6 DNS Services Hosting Primary Domain Service Secondary DNS DNS Forwarder

7 Web Caching improved fetch performance ISP cost reduction virtual web servers (virtual domains) proxy servers accepting advertisements on the web page

8 Caching GET 1 cache cache GET 2 GET

9 Large Scale Caching client Core Cache System cache server cache client ICP requests client cache cache server cache cache server ISP Network

10 POP Cache Architecture Redirect TCP port 80 requests to local cache system to customer sites LAN Switches Core Router Core Network Access s Cache s

11 Web Hosting Virtual web hosts user page user page user page user page sub 1 sub 2 sub 3 sub 4 sub 1 sub 2 sub 3 sub 4 sub 1 sub 2 sub 3 sub 4 sub 1 sub 2 sub 3 sub 4 sub 11 sub 12 sub 31 sub 32 sub 33 sub 4 sub 11 sub 12 sub 31 sub 32 sub 33 sub 4 sub 11 sub 12 sub 31 sub 32 sub 33 sub 4 sub 11 sub 12 sub 31 sub 32 sub 33 sub 4 sub 121 sub 321 sub 322 sub 121 sub 321 sub 322 sub 121 sub 321 sub 322 sub 121 sub 321 sub 322

12 USENET servers can be a valuable service can be expensive! too much traffic getting-in too much hard disk capacity maintenance cost a lot!

13 Games and Entertainment The Internet is not intended to be serious and there s a perfectly good market for games and entertainment Game servers Streaming audio/video servers

14 Local Office Local Office Local Office Upstream ISP Network Access Local Office Access Router Upstream Feed Router Access Filters Radius Mail DNS Cache Usenet Accounting Data Network Management

15 45Mbps Backbone 45Mbps Backbone Backbone Router Backbone Router Dial-Up Network Access Network Client Access Router Network Client Access Router Radius Mail DNS Cache Usenet Accounting Data Network Mgmt

16 622MbpsSONET Backbone Add Drop Mux Dial-Up Network Access s Backbone Router Backbone Router Fast Ethernet Switch Fast Ethernet Switch 155Mbps Fiber Connectors Network Client Access Routers Radius Mail DNS Cache Usenet Accounting Data Network Mgmt

17 Adding Security to the Design Service Plane Network Access Local Office Access Router Network Router Radius Mail DNS Cache Usenet Accounting Data Network Management Control and Management Plane

18 Local Office Local Office Example: Securing the the Usenet Local Office Network Carriage Plane Network Access Local Office Access Router Upstream Feed Router no loose source routing no directed broadcast permit any source to usenet server TCP port 119 permit NetOpsCenter source to usenet server deny all else Radius Mail DNS Cache Usenet ISP Service Plane ISP Management Plane TCP logging SYN protection permit any source connect to TCP port 119 permit NetOpsCenter source to any port deny all else Accounting Network Management

19 Service Issues Do ISP services attract a different tariff? How are service ports accounted?