Common Protocols
The protocol used for secure web browsing (port 443)
What is HTTPs?
The standard port # for HTTP
What is Port 80?
The command to view interface configuration in Cisco IOS (privileged exec)
“What is show running-config?” (show run)
The service that assigns IP addresses dynamically
What is DHCP?
A network device that filters traffic based on rules and can block specific ports or IP addresses.
What is a Firewall?
The protocol used for sending email
What is SMTP?
The port # for DNS (UDP)
What is port 53?
The protocol used to remotely configure network devices securely.
What is SSH?
The translation of private IPs to public IPs
What is "NAT"
A basic troubleshooting tool that tests connectivity by sending ICMP echo requests.
What is Ping?
DNS is primarily what kind of protocol (stateful/stateless)?
What is Stateless? ( Meaning a device self-assigns an address )
The port # for FTP data transfer (active mode)
What is port 20?
Mode required to commit changes in a Cisco switch (global config)
“What is global configuration mode?”
The management protocol that polls device statistics
What is "SNMP"? (Simple Network Management Protocol"
If devices on the same switch can’t communicate because they’re assigned to different VLANs, what’s likely misconfigured?
“What is the VLAN configuration?”
The protocol used to transfer files securely over SSH
"What is SFTP (SSH File Transfer Protocol)?”
Port number for SMTP
What is port 25?
The command to assign an IP address to an interface using the CLI
interface GigabitEthernet0/1; ip address 192.168.1.1 255.255.255.0 (or any made up useable address with a subnet mask )
The tunneling protocol often used for site-to-site VPNs
What is "IPsec"?
Two common authentication protocols used in secure network access, often in Wi-Fi or enterprise environments.
“What are RADIUS (Remote Authentication Dial-In User Service) and TACACS+?” (Terminal Access Controller Access-Control System )
The application-layer protocol used when you browse web pages (not secure)
What is HTTP?
Port # used for IMAP over SSL / TLS
(SSL - Secure Sockets Layer - Encrypted connection)
(TLS - Transport Layer Security - Successor to SSL)
What is port 993? (Secure encrypted email access)
The protocol that is insecure or unencrypted); AND why it’s insecure
Telnet (unencrypted, "clear text", easy to sniff)
How SNMP v3 improves security over v1/v2c
What is with (authentication and encryption vs community string)
Software or appliances like Wireshark or SolarWinds used to capture or analyze network traffic.
“What are network monitoring or packet analysis tools?”