---
manufacturer: Ciena
model: '3940'
slug: ciena-3940
part_number: 170-3940-901
u_height: 1
is_full_depth: false
front_image: true
weight: 3.6
weight_unit: kg
airflow: front-to-rear
console-ports:
  - name: CONSOLE
    type: de-9
module-bays:
  - name: PS A
    position: A
    description: |
      170-0100-901 AC PLUGGABLE POWER SUPPLY, 3940/3960
      170-0101-901 DC PLUGGABLE POWER SUPPLY, 3940/3960
  - name: PS B
    position: B
    description: |
      170-0100-901 AC PLUGGABLE POWER SUPPLY, 3940/3960
      170-0101-901 DC PLUGGABLE POWER SUPPLY, 3940/3960
interfaces:
  - name: '1'
    type: 1000base-x-sfp
  - name: '2'
    type: 1000base-x-sfp
  - name: '3'
    type: 1000base-x-sfp
  - name: '4'
    type: 1000base-x-sfp
  - name: '5'
    type: 1000base-x-sfp
  - name: '6'
    type: 1000base-x-sfp
  - name: '7'
    type: 1000base-x-sfp
  - name: '8'
    type: 1000base-x-sfp
  - name: '9'
    type: 1000base-x-sfp
  - name: '10'
    type: 1000base-x-sfp
  - name: '11'
    type: 1000base-x-sfp
  - name: '12'
    type: 1000base-x-sfp
  - name: '13'
    type: 1000base-x-sfp
  - name: '14'
    type: 1000base-x-sfp
  - name: '15'
    type: 1000base-x-sfp
  - name: '16'
    type: 1000base-x-sfp
  - name: '17'
    type: 1000base-x-sfp
  - name: '18'
    type: 1000base-x-sfp
  - name: '19'
    type: 1000base-x-sfp
  - name: '20'
    type: 1000base-x-sfp
  - name: '21'
    type: 1000base-x-sfp
  - name: '22'
    type: 1000base-x-sfp
  - name: '23'
    type: 1000base-x-sfp
  - name: '24'
    type: 1000base-x-sfp
  - name: MGMT
    type: 1000base-t
    mgmt_only: true