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ISP Services

Working at a Small-to-Medium Business or ISP – Chapter 7

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Objectives Describe the network services provided by an ISP

Describe the protocols that support the network services provided by an ISP

Describe the purpose, function, and hierarchical nature of Domain Name Service (DNS)

Describe and enable common services and their protocols.

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Network Services Provided by an ISP Identify the network services an ISP will provide to

SOHOs and medium-sized organizations

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Protocols that Support ISP Services Review the TCP/IP suite of protocols

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Protocols that Support ISP Services Explain why a protocol would use TCP

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The TCP Connection Process The three-way handshake

Retransmission

Sequencing

Flow Control

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Protocols that Support ISP Services Describe the differences between TCP and UDP ports

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Supporting Multiple Services Describe the purpose and function of TCP and UDP

ports

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Domain Name Service (DNS) Describe the purpose of networking naming system

srv2

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Domain Name Service (DNS) Describe the purpose and function of DNS.

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Domain Name Service (DNS) Describe the hierarchical design of DNS

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Domain Name Service (DNS) Describe the role of ISPs in the provisioning of DNS

service

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Services and Protocols Identify the most common services used on the Internet

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Services and Protocols Describe how an ISP supports the HTTP and HTTPS

protocols

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Services and Protocols Describe how an ISP supports the FTP protocol

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Services and Protocols Describe how the ISP supports the SMTP, POP3 and

IMAP protocols

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Summary

TCP and UDP use port numbers to provide multiple services to hosts.

DNS uses a hierarchical system of databases to resolve names and IP addresses of known hosts within networks and across the Internet.

The most common services used on the Internet include FTP, FTPS, HTTP, HTTPS and SMTP.

ISPs use high-performance servers to support these services.

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