Application Protocols

Question 1

What is Telnet?

Answer 1

•Provides command line interface between client and server •1 character per packet, unencrypted •Most network equipment, including Cisco, includes telnet client and server capability •UNIX based systems include client and optionally server •Putty is common Windows app providing Telnet client

Question 2

What is SSH?

Answer 2

Secure Shell ______________________ •Provides command line interface between client and server •1 character per packet, encrypted •Most network equipment, including Cisco, includes ssh client and server capability •UNIX based systems include client and server •Putty is common Windows app providing ssh client

Question 3

Describe FTP

Answer 3

•Supports unencrypted file transfer between client and server •SFTP supports secure file transfer •Supports directory management on client and server •Command line utility include on UNIX systems •Command line FTP included on Windows •GUI optional on Windows (CuteFTP) •SFTP optional on Windows (psftp - Putty)

Question 4

Describe TFTP

Answer 4

Trivial File Transfer Protocol ______________________ •Supports unencrypted file transfer between client and server •Does not support directory management on client and server •Often used to backup/restore network device configuration and IOS •Many free servers for UNIX and Windows system

Question 5

What is SNMP?

Answer 5

Simple Network Management Protocol ___________________________ •Supports data gathering, configuration changes, and alert trapping •Used extensively on network devices •Typically interfaces with network management system

Question 6

What is NTP?

Answer 6

Network Time Protocol ___________________ •Allows devices to time sync •Requires a time standard on the network •Can be provided on enterprise network or one of many public servers •Required for some authentication protocols •Allows log entries to be accurately time stamped •Allows timed job to start on time

Question 7

Describe hostnames and domains

Answer 7

•Supported by Domain Name Service (DNS) •Protocol that resolves names to IP •Worldwide unique namespace hierarchy •Top Level Domains (TLDs) maintained by ICANN •Second and lower level domains registered to owners •Known as delegation •Owners are “authoritative” for registered domain

Question 8

List some domain information yall:

Answer 8

•Data for a domain is called a zone •Primary zone - writable master copy •Secondary zone - read only replica of master •Secondary zones on separate servers provide high availability (HA) •Can have forward lookup zones - resolve name to IP •Can have reverse lookup zones - resolve IP to name •Zone files contain records •Records map names to IP or vice versa

Question 9

List three DNS record types:

Answer 9

•NS - Name Service identifies name of DNS server •A - IPv4 host record •AAAA - IPv6 host record •MX - Mail eXchange identities mail server (SMTP) •CNAME - Canonical name provides alias to host •PTR - Pointer provides reverse resolution

Question 10

What is DDNS?

Answer 10

Dynamic Domain Name System __________________________ •DNS records are automatically updated if an IP address changes •People often use this on home and SOHO networks when ISP changes public IP •Home routers often have this built in

Question 11

List three name resolution tools:

Answer 11

•NSlookup (name service lookup) •Can query any DNS server on the network •Can perform forward and reverse resolution •Can specify type of record to resolve •Interactive mode - make multiple lookups •Non-Interactive mode - make single lookup

Question 12

Can you label all the parts of a URL?

Answer 12

Now you can!

Question 13

What does URL stand for?

Answer 13

Uniform Resource Locator