Tài liệu, ebook Quản Trị Mạng

Transport layer of the TCP/IP stack Access to the network layer for applications Connection-oriented protocol Full-duplex mode operation Error checking Sequencing of data packets Acknowledgement of receipt Data-recovery features

30 trang | Chia sẻ: nguyenlam99 | Ngày: 09/01/2019 | Lượt xem: 1255 | Lượt tải: 1

VPNs (cont’d.) • PPTP (Point-to-Point Tunneling Protocol) – Microsoft • Encryption, authentication, access services – Dial directly into RRAS access server – Dial into ISP’s remote access server first • L2TP (Layer 2 Tunneling Protocol) – Cisco • Connects VPN using equipment mix • Connect two routers • Tunnel endpoints not on same packet-...

24 trang | Chia sẻ: nguyenlam99 | Ngày: 09/01/2019 | Lượt xem: 1366 | Lượt tải: 1

Gateway – Combinations of networking hardware and software • Connecting two dissimilar networks – Connect two systems using different formatting, communications protocols, architecture – Repackages information – Reside on servers, microcomputers, connectivity devices, mainframes • Popular gateways – E-mail gateway, Internet gateway, LAN ga...

24 trang | Chia sẻ: nguyenlam99 | Ngày: 09/01/2019 | Lượt xem: 1466 | Lượt tải: 1

Best Practices for Cable Installation and Management • Choosing correct cabling – Follow manufacturers’ installation guidelines – Follow TIA/EIA standards • Network problems – Often traced to poor cable installation techniques • Installation tips to prevent Physical layer failures

20 trang | Chia sẻ: nguyenlam99 | Ngày: 09/01/2019 | Lượt xem: 1544 | Lượt tải: 1

Facilitates newsgroup messages exchange – Between multiple servers, users • Similar to e-mail – Provides means of conveying messages • Differs from e-mail – Distributes messages to wide group of users at once • User subscribes to newsgroup server host • News servers – Central collection, distribution point for newsgroup messages

22 trang | Chia sẻ: nguyenlam99 | Ngày: 09/01/2019 | Lượt xem: 1722 | Lượt tải: 1

IEEE 802.3af standard – Supplying electrical power over Ethernet connections • Two device types – PSE (power sourcing equipment) – PDs (powered devices) • Requires Cat 5 or better copper cable • Connectivity devices must support PoE • Compatible with current 802.3 installations

19 trang | Chia sẻ: nguyenlam99 | Ngày: 09/01/2019 | Lượt xem: 1421 | Lượt tải: 1

Token ring – Developed by IBM – Relies upon direct links between nodes and ring topology – Nearly obsolete – Defined by IEEE 802.5 standard • Ethernet frames and token ring frames differ – Will not interact with each other – Devices cannot support more than one frame type per physical interface or NIC

13 trang | Chia sẻ: nguyenlam99 | Ngày: 09/01/2019 | Lượt xem: 1565 | Lượt tải: 1

Provide varying benefits – Connect with people having similar interests – New learning opportunities – Specialized information access – Tangible assets (free goods) – Publications – Technical workshops and conferences – Free software, prerelease software – Expensive hardware lab access

12 trang | Chia sẻ: nguyenlam99 | Ngày: 09/01/2019 | Lượt xem: 1225 | Lượt tải: 1

UNIX and Linux Command Sampler (cont’d.) • Most frequently used UNIX command – ls – Provides file information • Stores in file inode (information node) – ls –l command • Access permissions field • Files type designations • Pipe – Direct one command output to input of another command – Unix: vertical bar ( | )

22 trang | Chia sẻ: nguyenlam99 | Ngày: 09/01/2019 | Lượt xem: 1663 | Lượt tải: 1

A physical topology describes the layout for wiring the physical devices, while a logical topology describes how information flows through a network. There are three common methods of connecting the small office to the Internet: DSL using the existing telephone lines, cable using the CATV infrastructure, and serial links using the classic digital ...

23 trang | Chia sẻ: nguyenlam99 | Ngày: 09/01/2019 | Lượt xem: 1250 | Lượt tải: 1