ISR4321/K9 – 2x1G RJ45 (1 SFP Shared) – 2 NIM + 1 ISC Slots – ISR 4321 Branch Router
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ISR4321/K9 Description
The ISR4321/K9 is a Cisco 4000 Family Integrated Services Router, the ISR 4321, for small branch offices that route WAN traffic through modular interfaces. The router has two onboard Gigabit Ethernet ports, one of which can run as SFP, along with two NIM slots, an ISC slot for a PVDM4 voice DSP, 4 GB of DRAM and 50 Mbps of aggregate throughput that a performance license raises to 100 Mbps. Power comes from an external supply with no redundant option, and the onboard ports carry no PoE.
Quick Specs
|
Parameter |
Specification |
|---|---|
|
Onboard WAN or LAN ports |
2 x 10/100/1000 RJ-45; 1 SFP shares a port with its RJ-45 pair |
|
Management port |
1 dedicated Gigabit Ethernet port |
|
Module slots |
2 NIM slots and 1 onboard ISC slot; no SM-X slot |
|
Aggregate throughput |
50 Mbps default; 100 Mbps with FL-4320-PERF-K9 |
|
DRAM |
4 GB, upgradable to 8 GB |
|
Default flash |
4 GB, upgradable to 8 GB |
|
Default power supply model |
External AC power supply; 125W maximum system power |
|
Default PoE budget |
None; the default AC supply provides no PoE |
|
PoE with PWR-4320-POE-AC |
120W for endpoints, 260W platform maximum |
|
Redundant power supply |
Not available |
|
Software modes |
Autonomous or Catalyst SD-WAN controller mode on one universalk9 image from Cisco IOS XE 17.2.1 |
|
Encryption without HSEC |
1,000 secure tunnels and 250 Mbps of crypto bandwidth |
|
Form factor |
1RU, 1.75 x 14.55 x 11.60 in |
Product Performance
Key Features
Out of the box the router forwards 50 Mbps of aggregate traffic. A performance license, delivered remotely, doubles that to 100 Mbps without a hardware change, and a separate boost license applies to plain CEF routing over the onboard ports.
Each NIM slot connects to the route processor at up to 2 Gbps and has a second link for direct module-to-module traffic. LTE Advanced, voice and asynchronous serial modules fit these slots, and I/O modules can be replaced while the router stays powered.
The onboard ISC slot takes a PVDM4 voice DSP module, which mounts inside the chassis and leaves both NIM slots free. A PVDM4 handles conferencing, media optimization and transcoding, with up to 256 channels on the largest module.
From Cisco IOS XE 17.2.1 a single universalk9 image runs the router in autonomous mode or in Catalyst SD-WAN controller mode. Autonomous mode carries a perpetual license, while controller mode runs on a term license that needs renewal.
The two onboard Gigabit ports have no front-panel PoE+. Endpoint power comes from the optional PWR-4320-POE-AC supply, which gives up to 120W to endpoints within a 260W platform maximum. Four devices drawing 30W each use the full 120W.
The 1RU chassis is 14.55 in wide and 11.60 in deep, with mounting holes underneath for wall installation. Typical sound pressure is 24.2 dBA, and cooling air moves from the right side of the chassis to the left side.
Application Scenarios
A small branch office connects its LAN to an MPLS or broadband circuit through the onboard Gigabit ports, and the router handles routing, firewall and VPN for the site once the security package is licensed.
At a remote site served by a single wired circuit, an LTE Advanced NIM in one of the two NIM slots gives the router a cellular path to use when the primary link fails.
In an office whose IP phones register to a central call controller, the router terminates analog or BRI lines on voice NIMs and keeps phones working through SRST when the WAN goes down.
Product Comparison
|
Parameter |
ISR4321/K9 |
ISR4331/K9 |
ISR4221/K9 | |
|---|---|---|---|---|
|
Total onboard WAN or LAN 1G ports |
2 (2 RJ-45, 1 SFP) |
3 |
2 (2 RJ-45, 1 SFP) |
4 (2 RJ-45, 2 SFP) |
|
Aggregate throughput (default) |
50 Mbps |
100 Mbps |
35 Mbps |
Not published |
|
Aggregate throughput (performance license) |
100 Mbps |
300 Mbps |
75 Mbps |
Not published |
|
Module slots |
2 NIM, 1 ISC |
2 NIM, 1 SM-X, 1 ISC |
2 NIM |
1 NIM, 1 PIM |
|
DRAM |
4 GB (8 GB maximum) |
4 GB (16 GB maximum) |
4 GB fixed |
8 GB (32 GB maximum) |
|
Default power supply (model and wattage) |
External AC, 125W maximum system power |
Internal AC, 250W maximum system power |
External AC, 90W maximum system power |
PWR-CC1-100WAC 100W AC, integrated |
|
Default PoE budget |
0W |
0W |
Not applicable |
0W |
|
PoE budget with PoE power supply |
120W with PWR-4320-POE-AC |
250W |
Not applicable |
150W with PWR-CC1-150WAC |
ISR4321/K9 and ISR4331/K9 both have two NIM slots and an ISC slot, but ISR4331/K9 adds a third onboard port, an SM-X slot, an internal supply with a 250W PoE budget and 100 Mbps of default throughput against 50 Mbps. A branch that needs more than 100 Mbps, a service module or more than 120W of PoE belongs on that model, which licenses up to 300 Mbps. ISR4221/K9 tops out at 75 Mbps with fixed 4 GB DRAM and no PoE, so it fits sites that stay under 75 Mbps and power no endpoints. C8200-1N-4T offers four onboard ports, 8 GB of DRAM and a PIM slot, but only one NIM slot. Before any change of model, FL-4320-PERF-K9 lifts ISR4321/K9 from 50 Mbps to 100 Mbps.
Ordering Checklist
- Technology package: The base router runs IP Base only; add SL-4320-SEC-K9 for IPsec and firewall, SL-4320-UC-K9 for voice, or SL-4320-APP-K9 for MPLS and AVC. The license must match the features the branch will run.
- HSEC license: Add FL-4320-HSEC-K9 when the design needs more than 1,000 secure tunnels or full crypto functionality. The license requires the security package and has no evaluation period.
- Performance license: Order FL-4320-PERF-K9 when the site needs 100 Mbps of aggregate throughput. Without it the router stays at 50 Mbps.
- Memory and flash: MEM-4320-4GU8G takes DRAM from 4 GB to 8 GB and MEM-FLSH-4U8G takes flash from 4 GB to 8 GB. Both upgrades reach the chassis maximum.
- PoE power supply: Order PWR-4320-POE-AC when the router must power endpoints. The onboard Gigabit ports carry no PoE, and endpoint power is limited to 120W.
Optional Add-ons
|
Model |
Description |
|---|---|
|
PWR-4320-POE-AC |
AC power supply with PoE for the ISR 4320 series; up to 120W of endpoint PoE |
|
MEM-4320-4GU8G |
DRAM upgrade from 4 GB to 8 GB (fixed 4 GB plus an additional 4 GB) |
|
MEM-FLSH-4U8G |
eUSB flash upgrade from 4 GB to 8 GB for the ISR 4300 |
|
FL-4320-PERF-K9 |
Performance license raising aggregate throughput from 50 Mbps to 100 Mbps |
|
FL-4320-BOOST-K9 |
Boost performance license for CEF-only forwarding on the ISR 4320 series |
|
FL-4320-HSEC-K9 |
HSEC export compliance license for the ISR 4320 series |
|
SL-4320-SEC-K9 |
Security technology package license |
|
SL-4320-UC-K9 |
Unified Communications technology package license |
|
SL-4320-APP-K9 |
Application Experience technology package license |
|
32-channel voice DSP module for the onboard ISC slot | |
|
64-channel voice DSP module for the onboard ISC slot | |
|
NIM-LTEA-EA |
LTE Advanced Cat 6 NIM for the Americas, Europe and the Middle East |
|
24-port asynchronous serial NIM |
Front View
|
1 |
Grounding |
2 |
Power switch |
|
3 |
Power input connector |
4 |
GE “MGMT” port (with USB port below) |
|
5 |
USB Type B mini port |
6 |
Console port |
|
7 |
Auxiliary port |
8 |
GE 0/0/0 (copper cable) port |
|
9 |
GE 0/0/1 RJ-45 (copper cable) port |
10 |
GE 0/0/0 SFP (fiber-optic) port |
Rear View
|
1 |
NIM slots |
Specifications
| Parameter | Specification | Parameter | Specification |
|---|---|---|---|
| Product ID | ISR4321/K9 | Rack height | 1RU |
| Total onboard WAN or LAN 10/100/1000 ports | 2 | RJ-45-based ports | 2 |
| SFP-based ports | 1, sharing a physical port with the same-numbered RJ-45 port | Total onboard WAN or LAN 10Gbps ports | 0 |
| RJ-45 port standards | 10BASE-T, 100BASE-TX, 1000BASE-T | SFP port modules | 1000BASE-LX/LH, SX, ZX, CWDM and 100 Mbps SFP modules |
| Management port | 1 dedicated Gigabit Ethernet port | NIM slots | 2 |
| Enhanced service-module slots | 0 | Onboard ISC slot | 1, for PVDM4 voice DSP modules |
| OIR (all I/O modules) | Yes | Aggregate throughput (default) | 50 Mbps |
| Aggregate throughput (performance license) | 100 Mbps with FL-4320-PERF-K9 | Default memory DRAM | 4 GB |
| Maximum memory DRAM | 8 GB | Flash | 4 GB |
| Maximum flash memory | 8 GB | External USB 2.0 slots (type A) | 1 |
| USB console port (type B mini) | 1 | Serial console port (RJ-45) | 1 |
| Serial auxiliary port (RJ-45) | 1 | Power-supply options | External AC and external PoE (PWR-4320-POE-AC) |
| Redundant power supply | Not available | AC input voltage | 100 to 240 VAC autoranging |
| AC input frequency | 47 to 63 Hz | AC input current range | 1.5 to 0.6 A |
| Typical power (no modules) | 36W | Maximum power with AC power supply | 125W |
| Maximum power with PoE power supply (platform only) | 260W | Maximum endpoint PoE power from PoE power supply | 120W |
| Front-panel PoE+ on onboard ports | Not supported | External power supply dimensions | 2.95 x 1.18 x 6.10 in (75 x 30 x 155 mm) |
| Dimensions (H x W x D) | 1.75 x 14.55 x 11.60 in (44.55 x 369.57 x 294.64 mm) | Rack-mount 19 in. EIA | Included |
| Wall-mount | Mounting holes under chassis | Weight with AC PS (no modules) | 3.5 kg (7.7 lb) plus 0.66 kg (1.2 lb) external power supply |
| Typical weight (fully loaded with modules) | 4.2 kg (9.14 lb) plus 0.66 kg (1.2 lb) external power supply | Airflow | Right I/O side to left I/O side |
| MTBF | 593,270 hours | Operating temperature | 0°C to 40°C (32°F to 104°F) |
| Storage temperature | -40°C to 70°C (-40°F to 158°F) | Relative humidity | 5% to 85% operating; 5% to 95% nonoperating |
| Operating altitude | 0 to 3,050 m (10,000 ft); 0 to 2,000 m (6,560 ft) in China | Sound pressure (typical/maximum) | 24.2/51.9 dBA |
| Sound power (typical/maximum) | 31.9/59.9 dBA | Safety certifications | UL 60950-1, CAN/CSA C22.2 No. 60950-1, EN 60950-1, AS/NZS 60950-1, IEC 60950-1 |
| EMC certifications | ICES-003 Class A, EN55032 Class A, CISPR32 Class A, AS/NZS CISPR 32 Class A, VCCI V-3, CNS 13438, EN 300-386, EN 55024, CISPR 24 | Software image | universalk9; autonomous and Catalyst SD-WAN controller mode from Cisco IOS XE 17.2.1 |
| Technology packages | IP Base by default; Security, Unified Communications and Application Experience by license | Crypto limits without HSEC | 1,000 secure tunnels and 250 Mbps of crypto bandwidth |
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Quality Certifications
Customer Reviews
Questions & Answers
-
Which ROMMON release does ISR4321/K9 need for IOS XE 16.9 and for IOS XE 17.6?
-
Which PVDM4 modules can ISR4321/K9 take in its ISC slot?
-
How many NIM-16A or NIM-24A modules can ISR4321/K9 hold?
-
Which bundle PIDs exist for ISR4321/K9 with licenses preinstalled?
-
Which spare part PIDs are listed for ISR4321/K9?
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