paultclark.com

Protocols



Address Resolution Protocol (ARP)


Domain Name System (DNS)


Dynamic Host Configuration Protocol (DHCP)


File Transfer Protocol (FTP)

  • FTP is a standard network protocol used for the transfer of computer files between a client and server on a computer network.
  •  
  • Commands
      binarySets the file transfer type to binary. Critical to the successful transfer of files such as Word documents, graphics, or software packages; also works fine with text files (files that contain only ascii text and no formatting).
      get $filenameTransfers a file from a remote computer to the computer you are typing on.
      mget $file1 $file2Transfers multiple files from a remote computer to the computer you are typing on.
      lsLists all the files in your current sub-directory.
      cdChanges the directory. To move back up to a previous level, use \"cd ..\" (note the space).
      put $filenameTransfers a file from the computer you are typing on to the remote computer.
      mput $file1 $file2Transfers multiple files from the computer you are typing on to the remote computer.
      pwdTells you the present working directory.
      <Ctrl>+hDeletes a character to the left of the cursor (acts as a backspace). Note: Use the Ctrl key; don't type the word "Ctrl".
      help $commandDisplays the definition of a command. Type \"help\" to see a full list of valid commands.
      byeEnds the FTP session.
  • External Links


Hypertext Transfer Protocol (HTTP) / Hypertext Transfer Protocol Secure (HTTPS)


Internet Message Access Protocol (IMAP)

  • IMAP is an Internet standard protocol used by e-mail clients to retrieve e-mail messages from a mail server over a TCP/IP connection.
  •  
  • External Links


Internet Protocol version 4 (IP) / Internet Protocol version 6 (IPv6)

  • IP is the principal communications protocol in the Internet protocol suite for relaying packets across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet.
  •  
  • Special Use Subnets
      0.0.0.0/8self-identification
      10.0.0.0/8Private
      127.0.0.0/32Loopback
      169.254/16DHCP link local address
      172.16.0.0/12Private
      192.0.0.0/24Special Purpose
      192.0.2.0/24TEST-NET-1
      192.88.99.0/246to4 relay anycast
      192.88.99.2/326to4 relay anycast
      192.88.99.2/326to4 relay anycast
      192.168.0.0/16Private
      198.18.0.0/15Interconnect Device
      198.51.100.0/24TEST-NET-2
      203.0.113.0/24TEST-NET-3
      224.0.0.0/4Multicast
      240.0.0.0/4Reserved
      255.255.255.255/32Limited broadcast
      fc00::/7Unique Local Unicast
      fe80::/10Link Local Unicast
      ff00::/8Multicast
  •  
  • IP Assignment
  •  
  • External Links


Lightweight Directory Access Protocol (LDAP)

  • LDAP is an open, vendor-neutral, industry standard application protocol for accessing and maintaining distributed directory information services over an Internet Protocol (IP) network.
  •  
  • Commands
      ldapbindUse ldapbind to authenticate to a directory server or find out if the server is running.
      ldapsearchUse ldapsearch to search for specific entries in a directory. ldapsearch opens a connection to a directory, authenticates the user performing the operation, searches for the specified entry, and prints the result in a format that the user specifies.
      ldapaddUse ldapadd to add entries to the directory. ldapadd opens a connection to the directory and authenticates the user. Then it opens the LDIF file supplied as an argument and adds, in succession, each entry in the file.
      ldapdeleteUse ldapdelete to remove leaf entries from a directory. ldapdelete opens a connection to a directory server and authenticates the user. Then it deletes specified entries.
      ldapmodifyUse ldapmodify to modify existing entries. ldapmodify opens a connection to the directory and authenticates the user. Then it opens the LDIF file supplied as an argument and modifies the LDAP entries specified by the file.
      ldapmoddnUse ldapmoddn to change the RDN of an entry or move an entry or subtree to another location in the directory
  •  
  • External Links


Network File System (NFS)

  • NFS is a distributed file system protocol allows a user on a client computer to access files over a computer network much like local storage is accessed.
  •  
  • External Links


Network Time Protocol (NTP)

  • Network Time Protocol (NTP) is a networking protocol for clock synchronization between computer systems over packet-switched, variable-latency data networks.
  •  
  • External Links


Post Office Protocol version 3 (POP3)

  • POP is an application-layer Internet standard protocol used by e-mail clients to retrieve e-mail from a server in an Internet Protocol (IP) network.
  •  
  • Commands
      USER Your user name for this mail server
      PASS Your password.
      QUITEnd your session.
      STATNumber and total size of all messages
      LIST Message# and size of message
      RETR $messageRetrieve selected message
      DELE $messageDelete selected message
      NOOPNo-op. Keeps you connection open.
      RSETReset the mailbox. Undelete deleted messages.
  •  
  • External Links


Real-time Transport Protocol (RTP)


Secure Shell (SSH)

  • SSH is a cryptographic network protocol for operating network services securely over an unsecured network.
  •  
  • External Links


Simple Mail Transfer Protocol (SMTP)

  • SMTP is an Internet standard for electronic mail (email) transmission. Some ways to deal with Spam.
  •  
  • Commands
      ATRNAuthenticated TURN
      AUTHAuthentication
      BDATBinary data
      BURLRemote content
      DATAThe actual email message to be sent
      This command is terminated with a line that contains only a
      EHLOExtended HELO
      ETRNExtended turn
      EXPNExpand
      HELOIdentify yourself to the SMTP server.
      HELPShow available commands
      MAILSend mail from email account
      MAIL FROM: me@mydomain.com
      NOOPNo-op. Keeps you connection open.
      ONEXOne message transaction only
      QUITEnd session
      RCPTSend email to recipient
      RCPT TO: you@yourdomain.com
      RSETReset
      SAMLSend and mail
      SENDSend
      SOMLSend or mail
      STARTTLS
      SUBMITTERSMTP responsible submitter
      TURNTurn
      VERBVerbose
      VRFYVerify
  •  
  • External Links


Simple Network Management Protocol (SNMP)

  • SNMP is used to communicate management information between the network management stations and the agents in the network elements.
  •  
  • SNMP Security Levels

      Version

      Level

      Authentication

      Encryption

      What Happens

      v1 noAuthNoPriv Community String No Uses a community string match for authentication.
      v2c noAuthNoPriv Community String No Uses a community string match for authentication.
      v3 noAuthNoPriv Username No Uses a username match for authentication.
      v3 authNoPriv Message Digest Algorithm 5 (MD5) or Secure Hash Algorithm (SHA) No Provides authentication based on the Hashed Message Authentication Code (HMAC)-MD5 or HMAC-SHA algorithms.
      v3 authPriv Message Digest Algorithm 5 (MD5) or Secure Hash Algorithm (SHA) Data Encryption Standard (DES) Provides authentication based on the HMAC-MD5 or HMAC-SHA algorithms. In addition to authentication, provides DES 56-bit encryption based on the Cipher Block Chaining (CBC)-DES (DES-56) standard.
  •  
  • External Links


Spanning Tree Protocol (STP) / Rapid Spanning Tree Protocol (RSTP)

  • STP is a network protocol that builds a logical loop-free topology for Ethernet networks.
  •  
  • External Links
    • IEEE 802.1D IEEE standard for local and metropolitan area networks--Media access control (MAC) Bridges (for STP and RSTP).
    • IEEE 802.1Q IEEE Standards for local and metropolitan area networks-—Virtual Bridged Local Area Networks (for MSTP).
    • Wireshark
    • wikipedia


Transmission Control Protocol (TCP)


User Datagram Protocol (UDP)

  • UDP allows computer applications to send messages to other hosts on an Internet Protocol (IP) network. UDP has no handshaking. UDP packets are dropped on congested networks. Therefore, it is unclear if the message is delivered.
  •  
  • External Links