Cisco ISR 4331 Router with PVDM4-32 & Voice License
Inclusive of VAT · Warranty included
CISCO
Product Specification
| Product Family | Cisco ISR 4000 Series (4300) |
| Form Factor | 1U rack-mountable |
| Operating System | Cisco IOS XE |
| Onboard Network Ports | 3x Gigabit Ethernet |
| NIM Slots | 2 |
| SM-X Slots | 1 |
Refurbished · Tested
Cisco ISR 4331 branch router with a PVDM4-32 voice DSP module and voice licence, for WAN routing and voice gateway duties.
This refurbished Cisco ISR 4331 is a 1U branch router from the ISR 4000 Series (4300 models), running Cisco IOS XE. It is supplied with a Cisco PVDM4-32 voice DSP module and a voice licence, and is listed under SKU SD-CISCO-ISR4331-PVDM32-VOICE. Three onboard Gigabit Ethernet ports handle WAN and LAN links. Two NIM slots and one SM-X slot take further interfaces such as T1/E1, FXS/FXO or switch modules. Network and telephony teams in Qatar buy this configuration when one box must route the branch WAN and act as the voice gateway. The PVDM4-32 provides the DSP resources for TDM-to-IP conversion, transcoding and conferencing. That lets the router terminate PSTN circuits locally, keep analogue lines for fax or door phones, and provide survivable call handling alongside a central Cisco call control platform. We hold these units in Doha for branch rollouts and like-for-like replacements.
SD-CISCO-ISR4331-PVDM32-VOICEForm factor 1U rackSpecification
The throughput figure is aggregate traffic through the router, not port line rate: the Gigabit Ethernet ports still link at 1 Gb/s. The 300 Mb/s figure needs Cisco's optional performance licence and no hardware change.
| Model | NIM slots | SM-X slots | Throughput |
|---|---|---|---|
| ISR 4321 | 2 | None | Lower than ISR 4331 |
| ISR 4331 | 2 | 1 | 100 Mb/s, licensable to 300 Mb/s |
| ISR 4351 | 3 | 2 | Higher than ISR 4331 |
What is included
One Cisco ISR 4331 router, supplied with a Cisco PVDM4-32 voice DSP module and a Cisco voice licence.
Installation
The ISR 4331 is 1U and mounts in a standard 19 inch rack. Fit any NIM or SM-X interface modules with the router powered down, using an anti-static strap. The PVDM4-32 only supplies processing: physical voice ports come from NIMs, typically a T1/E1 voice NIM for ISDN PRI, or FXS and FXO NIMs for analogue phones, fax machines and analogue trunks. A call control platform or local gateway configuration is also required before calls will pass. Initial setup is through the console port, and configuration follows familiar IOS command syntax under IOS XE.
Licensing note
This router is supplied with a voice licence on Cisco IOS XE. Features such as CUBE session handling or local call control depend on the specific Cisco licences installed. After first power-up, the IOS XE licensing show commands display which licences are active, so check them against the planned deployment before go-live. The performance licence that raises throughput from 100 Mb/s to 300 Mb/s is optional and separate from the voice licence.
Part numbers and identification
Condition & testing
- Powered on and boot verified
- Ports tested, configuration reset to factory defaults
- Fully working; minor cosmetic marks are possible on refurbished units.
- 6-month warranty on every unit we sell, with installation and support across Qatar.
What ships with this device
Images are for illustration. The unit supplied is the one described in the specification and may differ cosmetically.
Our team in Doha answers specification and compatibility questions during working hours.
Ask on WhatsApp sales@serverdove.comWhat does the PVDM4-32 do in an ISR 4331?
The PVDM4-32 is a DSP module that provides processing for voice functions. These include converting TDM calls from T1/E1, FXS or FXO interfaces to IP, transcoding between codecs, and hardware conferencing. Without DSP resources the router cannot terminate traditional voice circuits. The module rates up to 32 channels, and the real figure falls as codec complexity rises.
How many simultaneous calls can the PVDM4-32 handle?
It supports up to 32 channels. That figure applies to low-complexity codecs such as G.711. Medium- and high-complexity codecs, transcoding and conferencing each use more DSP resource per session, so the usable count is lower. Cisco's DSP calculator gives an exact figure for a specific mix of codecs and services.
What throughput does the ISR 4331 support?
The ISR 4331 forwards 100 Mb/s of aggregate throughput as standard. An optional Cisco performance licence raises this to 300 Mb/s, with no hardware change. The figure is aggregate traffic through the router. It is not the line rate of the Gigabit Ethernet ports, which still link at 1 Gb/s.
How does the ISR 4331 differ from the ISR 4321 and ISR 4351?
The ISR 4321 is the smaller model. It has 2 NIM slots and no SM-X slot, and lower throughput. The ISR 4351 is larger, at 2U, with 3 NIM slots, 2 SM-X slots and higher throughput. The ISR 4331 sits between them, with 2 NIM slots, 1 SM-X slot and 100 Mb/s throughput that can be licensed up to 300 Mb/s.
What else is needed to connect PSTN or analogue lines?
The DSP module only provides processing resources. Physical voice ports come from interface modules fitted in the NIM slots. Typical choices are a T1/E1 voice NIM for ISDN PRI, or FXS and FXO NIMs for analogue phones, fax machines and analogue trunks. A call control platform or local gateway configuration is also required.
Which voice licence is included?
A voice licence is supplied with this router. The exact licence type should be confirmed before deployment, as features such as CUBE session handling or local call control depend on the specific Cisco licences installed. Check the licence state with the IOS XE licensing show commands once the router is powered up.
What operating system does the ISR 4331 run?
The ISR 4331 runs Cisco IOS XE, the same operating system used across the ISR 4000 Series. Configuration follows familiar IOS command syntax. IOS XE also supports the licensing model used to unlock the performance upgrade and feature packages, including voice.
What does refurbished mean at ServerDove?
Off-lease or decommissioned enterprise hardware that we clean, test and reset in Doha. Every unit goes through POST, burn-in, memory and drive checks and a power-supply check, with firmware and BIOS returned to defaults and drives securely erased.
Can I ask about the exact unit before I buy?
Yes. Message us the SKU on WhatsApp and we will confirm the condition and configuration of the unit in stock, with photos if you want them.
How fast is delivery in Qatar?
Orders ship from Doha and arrive within one working day anywhere in Qatar. Delivery is free on orders over QAR 300.
Can I collect in person?
Yes, from Nuaija Office 7, Doha, usually within 24 hours of ordering. Choose pick-up at checkout and we will message you when it is ready.
What warranty is included?
A 6-month hardware warranty from the delivery date, covering the unit as supplied. If a part fails we repair or replace it. Full terms are on the warranty page.
What is your return policy?
If the unit arrives faulty or not as described, tell us and we will collect it and replace or refund it. Full terms are on the Refund Policy page.
Which payment methods do you accept?
Visa, Mastercard and American Express online. Bank transfer is available for company orders; contact us for details.
Do prices include VAT?
Yes, all prices shown include VAT, and every order ships with a tax invoice.
Why buy refurbished
Enterprise hardware, tested in Doha, at a fraction of the price of new
Every unit we sell has already proven itself in a data centre. We test it again, grade it, and back it with a warranty before it leaves our stock.
Tested before it ships
POST, burn-in, memory and power-supply checks on every unit. Anything that fails is repaired or pulled from stock, not sold.
Same performance, lower cost
A Xeon runs the same workloads whether it is new or two years old. Spend the difference on more CPUs, memory or storage.
In stock, not on order
New enterprise hardware can take weeks or months to arrive. Ours is on the shelf in Doha and delivered across Qatar within a day.
Warranty and local support
Every unit is covered. Installation, configuration and hardware support are handled by our own team in Qatar, not a call centre abroad.