CITA 310 Section 8 Extending the Web Environment (Textbook Chapter 9)

Understanding FTP Services FTP is used to transfer files from a server to a client (download) and transfer files from a client to a server (upload) FTP client is the browser Also command-line and GUI clients FTP servers can operate as anonymous servers or they can require a valid logon Typically, they are anonymous FTP servers are not secure; user names and passwords are not sent encrypted

Understanding FTP Services The client connects to port 21 (control port) Port 20 (data port) is used to tell the client which unprivileged port to use for data transfer The above describes passive mode FTP, the most common type

Communicating with FTP Command Description Example ftp host Initiates a connection to FTP server ftp open host Once the FTP client has been started, opens a connection open close Closes the connection but does not exit the FTP client close quit or bye Closes the connection and exits the FTP client bye ls filenames Displays filenames and can use wildcards ls *.rpm dir filenames Displays the long listing of files and their properties, such as the size and date the file was created dir *.rpm

Communicating with FTP Command Description Example binary Transfer files in binary mode binary ascii Transfer files in text mode ascii get filename Downloads a single file get test.rpm put filename Uploads a single file put testapp.zip mget filenames Downloads multiple files; used with wildcards mget sendmail*.rpm mput filenames Uploads multiple files; used with wildcards mput *.tif prompt no Stops prompting for each file when used before you use mget or mput prompt no prompt Starts prompting prompt

Communicating with FTP Command Description Example hash Displays a hash symbol as files are being downloaded hash cd directory Moves to another directory on the FTP server cd /software lcd directory Moves to another directory on the client lcd /docs pwd Displays the current directory on the server pwd help command Finds very brief help on FTP commands; if used without a reference to a command, it will give you a list of commands available help mget

Understanding News Servers News servers allow threaded discussions You post messages in a newsgroup A newsgroup focuses on a single topic There are hundreds of gigabytes of information generated per day News servers can be set up for use within an organization

Telnet and Windows Telnet is not popular in Windows because telnet is text-based and Windows relies on a GUI However, there are many command-line utilities that can be used Before Windows, Microsoft networking depended on a single command net with many options cacls can be used to alter permissions netsh starts a networking shell which allows you to configure and display many network-related items

Common net Commands CommandDescriptionExample net user Lists all users net user net user username Displays user information net user mnoia net start service Starts a service net start "FTP Publishing Service" net share name=location Shares a folder net share docs=c:\docs net use drive: \\computer\share Maps a drive net use g: \\web1\docs

cacls options The format is: cacls file or folder name [options] OptionDescription /e Changes instead of replaces permission /t Changes all subfolders /g user:perm Grants a user specific permissions Permissions are: f (full control) r (read) w (write) c (change) n (none) /p user:perm As above, except permissions are replaced /r user /e Revokes permission

netsh Examples Create a text file with commands to re- create the IP configuration netsh interface ip dump Ping the gateway IP address of each NIC netsh diag ping gateway

Understanding Streaming Media Services Used to transfer video and audio By default, UDP is used Although TCP and HTTP can be used because of firewall issues in an organization No single standard exists as is true with HTTP, SMTP, POP3, and others Broadcast methods unicast – each packet is sent individually to each client multicast – each packet is sent to many clients