Acronyms
This protocol automatically assigns IP addresses, subnet masks, gateways, and DNS servers.
DHCP
This secure remote-management protocol normally uses TCP port 22.
SSH
This protocol prevents Layer 2 loops by placing redundant switch ports into a blocking state.
STP
This attack redirects local traffic by associating the gateway’s IP address with the attacker’s MAC address.
ARP poisoning
This layer transmits raw bits through cables, fiber, and wireless signals.
Layer 1 Physical
This protocol provides port-based network access control and often works with RADIUS.
802.1X
This protocol uses TCP port 179 to exchange routes between autonomous systems.
BGP
This switch port carries traffic for multiple VLANs using 802.1Q tags.
trunk port
This security model continuously evaluates identity, device health, location, and other conditions before allowing access.
Zero Trust
This first-hop redundancy protocol is a Cisco alternative to the vendor-neutral VRRP.
HSRP
This protocol synchronizes clocks and normally uses UDP port 123.
NTP
This technology combines multiple physical Ethernet links into one logical connection.
LACP
This secure directory protocol normally uses TCP port 636.
LDAPS
This architecture separates network control decisions from packet forwarding.
SDN
This VPN protocol uses UDP port 500 for initial key negotiation and UDP 4500 when NAT traversal is needed.
IKE/IPSEC
This attack creates a fraudulent wireless access point using the same SSID as a legitimate network.
Evil Twin