Port-naming in Cisco Router

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1. Naming Convention — The Rule

Cisco interface names are built from three parts (simple form used on many modular routers):

<Type><Slot>/<Port>

  • Type = Ethernet, FastEthernet, GigabitEthernet, Serial, etc.

  • Slot = the module slot number in the router chassis where the network module or WIC is inserted. Packet Tracer numbers these 0,1,2,... as you inserted modules.

  • Port = the physical port index on that module (usually 0 for single-port modules; multi-port modules will show 0,1,2...).

Notes:

  • Some platforms add a third number (e.g., GigabitEthernet0/0/0) — that’s slot/subslot/port on other platforms. For CCNA labs you’ll most often see Type slot/port.

  • Subinterfaces use a dot: GigabitEthernet2/0.10 (common for router-on-a-stick / VLANs).

2) Map Your Modules → show output

You gave these module descriptions and the show ip int brief list. Here’s the direct mapping (based on slot number ordering Packet Tracer uses):

Module (your list)
Displayed interface name

PT-ROUTER-NM-1CE

(single Ethernet)

Ethernet0/0

PT-ROUTER-NM-1CFE

(single FastEthernet copper)

FastEthernet1/0

PT-ROUTER-NM-1CGE

(single Gigabit with GBIC slot)

GigabitEthernet2/0

PT-ROUTER-NM-1FFE

(single FastEthernet fiber)

FastEthernet3/0

PT-ROUTER-NM-1FGE

(single Gigabit fiber/copper via GBIC)

GigabitEthernet4/0

Dual-serial WIC

(two serial ports)

Serial5/0 (and Serial5/1 if the second port is enabled/seen)

So your show ip int brief matches exactly the modules in slots 0..5:

Cisco Packet Tracer (Version 6.2.0.0052)

65KB
Port-naming-in-Cisco-Router.pkt
Open

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Keywords

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