The OSI Model

Network (Protocols and Standards)

ARP, ICMP, IGMP, IP, IPSec, RARP

Presentation Layer (Duties)

Allows hosts and applications to use a common language; performs data formatting, encryption, and compression.

Layer 2

Data Link Layer #

Transport Layer (Duties)

Ensures accurate delivery of data through flow control, segmentation and reassembly, error correction, and acknowledgement.

Data Link (Protocols and Standards)

L2TP, PPP, PPTP, SLIP

Presentation (Protocols and Standards)

MIME, SSL, TLS

Layer 3

Network Layer #

Data Link Layer (Duties)

Packages data in frames appropriate to network transmission method.

Layer 1

Physical Layer #

Session (Protocols and Standards)

RTP & SIP

Layer 5

Session Layer #

Transport (Protocols and Standards)

TCP & UDP

Layer 7

Application Layer #

Application (Protocols and Standards)

BOOTP, DHCP, DNS, FTP, HTTP, HTTPS, IMAP4,PING, POP3, NSLOOKUP, NTP, SFTP, SMTP, SNMP, Telnet, TFTP

Network Layer (Duties)

Establishes network connections; translates network addresses into their physical counterparts and determines routing.

Session Layer (Duties)

Establishes, maintains, and terminates user connections.

Physical Link (Standards)

IEEE 802.3 (Ethernet), 802.5 (Token Ring), 802.11 (Wi-Fi)

Physical Layer (Duties)

Manages signaling to and from physical network connections.

Layer 6

Presentation Layer #

Application Layer (Duties)

Provides Interface between software applications and network for interpreting application requests and requirements. *Note: This layer is not the actual software application.

Layer 4

Transport Layer #