Juniper Switches: EX Series Module Guide

Last updated: September 2026. Module specifications and platform compatibility re-checked against Juniper’s hardware documentation and data sheets; lifecycle status added for every platform from Juniper’s published EX Series end-of-life milestones, including the June 2026 end-of-life announcements for the EX4600 and EX4300-48MP.

Juniper’s fixed-configuration EX Series switches take optional plug-in modules that add uplink or expansion ports to the base chassis. Which module fits which switch is not always obvious from the part number, and several modules are restricted to specific models within a series. This guide lists every uplink and expansion module for the EX3200, EX4200, EX4300, EX4500, EX4550, and EX4600, plus the current EX4400 extension modules, what each one provides, which switch models accept it, and where each platform stands in Juniper’s lifecycle. A compatibility table is at the end.

Juniper EX Series Switch Modules Overview

Juniper uses two different terms for these modules. Uplink modules (part numbers beginning EX-UM or EX4500-UM) are found on the access-layer EX3200, EX4200, EX4300, and EX4500, and are intended to connect the switch to the distribution or core layer at a higher speed than the front-panel access ports. Expansion modules (part numbers containing EM) are found on the EX4550 and EX4600, where the base switch already has 10GbE ports and the module simply increases port density or adds 40GbE. In practice either type can be used for any purpose; the distinction is about the switch’s role rather than a technical limitation.

Juniper’s hardware guides classify these modules as hot-insertable and hot-removable field-replaceable units, meaning they can be installed or removed without powering down the switch. Optical transceivers are sold separately for every optical module listed here.

Lifecycle status: all of the platforms in this guide are now past their last order date with Juniper, and most are also past end of support, which is one reason they are widely available on the secondary market. Per Juniper’s published EX Series end-of-life milestones, the EX3200 reached end of support on August 31, 2019, the EX4500 by December 31, 2022 (earlier for some SKUs), and the EX4200 and EX4550 on June 30, 2024. The EX4300 24- and 48-port models (excluding the 48MP) had a last order date of March 31, 2024 and reach end of support on March 31, 2029; the EX4300-32F had a last order date of March 31, 2026 and also reaches end of support on March 31, 2029. On June 29, 2026, Juniper announced end of life for the EX4600 and the EX4300-48MP, with a last order date of December 29, 2026 and end of support on December 29, 2031. Dates by part number are on our Juniper end of life list, and our end of life vs end of service article explains what each milestone means.

Modules for EX3200 and EX4200 Juniper Switches

The EX3200 and EX4200 are 1GbE access switches; the EX4200 adds Virtual Chassis support. Both have a single front-panel uplink module slot, and the same four uplink modules fit both platforms:

• EX-UM-4SFP – 4-port 1GbE SFP uplink module
• EX-UM-2X4SFP – dual-mode 2-port 10GbE SFP+ / 4-port 1GbE SFP uplink module
• EX-UM-2X4SFP-M – the same dual-mode module with MACsec support
• EX-UM-2XFP – 2-port 10GbE XFP uplink module

EX-UM-4SFP

The simplest option: four 1GbE ports that accept SFP transceivers. It suits closets where the uplink to the distribution layer is still 1GbE fiber or where multiple 1GbE uplinks are bundled in a LAG.

EX-UM-2X4SFP and EX-UM-2X4SFP-M

These are dual-mode modules with four physical ports. In 1GbE mode all four ports are active and accept SFP transceivers; in 10GbE mode only two ports are active and they accept SFP+ transceivers. The mode is set in software and applies to the whole module, so a single module cannot run 1GbE and 10GbE uplinks at the same time.

The two part numbers are otherwise identical. The EX-UM-2X4SFP-M adds MACsec (IEEE 802.1AE) support, which encrypts traffic hop-by-hop on the uplink itself. This matters for links that leave a secured room or building, for example fiber runs between campus buildings, and for environments with compliance requirements for encryption in transit.

EX-UM-2XFP

Two 10GbE ports in the older XFP form factor. XFP transceivers are larger than SFP+ and are not interchangeable with them, and XFP ports do not accept 1GbE optics. This module is mainly of interest where an existing installation already uses XFP optics at the distribution end of the link; for a new 10GbE uplink the EX-UM-2X4SFP is the more flexible choice.

Juniper Switch Modules for the EX4300

The EX4300 is a 1GbE (and, on the 48MP, multigigabit) access switch with built-in 40GbE QSFP+ ports on the rear (four on the 24- and 48-port models, two on the EX4300-32F) that are used for Virtual Chassis or, on all models except the 48MP, as network ports. It also has a single front-panel uplink module slot. Unlike the EX3200 and EX4200, the EX4300 uplink modules are model-specific: per Juniper’s EX4300 hardware documentation, the module you can use depends on which EX4300 you have.

• EX-UM-4X4SFP – 4-port 1GbE/10GbE SFP+ uplink module for the 24- and 48-port models (EX4300-24T, -24P, -48T, -48P and their -S, -AFI, and -DC variants)
• EX-UM-8X8SFP – 8-port 1GbE/10GbE SFP+ uplink module for the EX4300-32F, -32F-S, and -32F-DC only
• EX-UM-2QSFP – 2-port 40GbE QSFP+ uplink module for the EX4300-32F, -32F-S, and -32F-DC only
• EX-UM-4SFPP-MR – 4-port 1GbE/10GbE SFP+ uplink module for the EX4300-48MP and -48MP-S only
• EX-UM-2QSFP-MR – 2-port 40GbE QSFP+ uplink module for the EX4300-48MP and -48MP-S only; from Junos OS 19.3R1 it also accepts 100GbE QSFP28 transceivers

EX-UM-4X4SFP

Four ports that accept SFP or SFP+ transceivers in any mix, so 1GbE and 10GbE uplinks can run side by side on the same module. This is the module for the common EX4300-24T/24P/48T/48P access switches. Note that it is not supported on the EX4300-32F or the EX4300-48MP.

EX-UM-8X8SFP

Eight ports that accept SFP or SFP+ transceivers in any mix. It is supported only on the EX4300-32F fiber models, where it brings the switch to 40 front-panel SFP/SFP+ ports.

EX-UM-2QSFP

Two 40GbE QSFP+ ports, again supported only on the EX4300-32F models. Combined with the two built-in rear QSFP+ ports on the EX4300-32F, this gives the switch up to four 40GbE ports, which is why it is often used as a small aggregation switch rather than a pure access switch.

EX-UM-4SFPP-MR and EX-UM-2QSFP-MR

The multigigabit EX4300-48MP uses its own pair of uplink modules, which are not interchangeable with the modules above. The EX-UM-4SFPP-MR provides four SFP/SFP+ ports and the EX-UM-2QSFP-MR provides two QSFP+ ports that can also take QSFP28 100GbE transceivers on Junos OS 19.3R1 or later. On the 48MP the rear QSFP+ ports are dedicated Virtual Chassis ports and cannot be used as network ports, so the uplink module is the only way to get 40GbE or 100GbE uplinks from that model. These two modules are included in Juniper’s June 2026 EX4300-48MP end-of-life announcement.

Modules Available for Juniper EX4500 Switches

The EX4500 is a 10GbE top-of-rack and aggregation switch with 40 fixed 1GbE/10GbE SFP/SFP+ ports and two front-panel uplink module slots. With both slots populated it reaches 48 SFP/SFP+ ports. It is well past end of support (the last EX4500 SKUs reached end of support on December 31, 2022, and earlier SKUs before that), so it is strictly a spares and legacy-replacement platform today.

• EX4500-UM-4XSFP – 4-port 10GbE SFP+ uplink module
• EX4500-VC1-128G – 128 Gbps Virtual Chassis module

EX4500-UM-4XSFP

Four SFP+ ports. Either or both of the two front slots can be populated, for a total of up to eight additional 10GbE ports.

EX4500-VC1-128G

The Virtual Chassis module installs in the rear of the chassis and provides two dedicated 64 Gbps Virtual Chassis ports (128 Gbps total). The EX4500-40F-VC1 base SKUs (-VC1-FB, -VC1-BF, and -VC1-DC) ship with it pre-installed; the other EX4500 SKUs do not include it. If you need to join an EX4500 to a Virtual Chassis with EX4200 or EX4550 members, the simplest path is to buy a -VC1 model.

Juniper EX4550 Switch Modules

The EX4550 is a 32-port 10GbE aggregation switch, available with 32 SFP/SFP+ ports (EX4550-32F) or 32 100M/1G/10GBASE-T copper ports (EX4550-32T). It has two expansion slots, one on the front and one on the rear, and reaches 48 ports with both populated. The EX4550 and all of its modules reached end of support on June 30, 2024.

• EX4550-EM-8XT – 8-port 100M/1G/10GBASE-T expansion module
• EX4550-EM-8XSFP – 8-port 10GbE SFP+ expansion module
• EX4550-EM-2QSFP – 2-port 40GbE QSFP+ expansion module
• EX4550-VC1-128G – 128 Gbps Virtual Chassis module

EX4550-EM-8XT

Eight RJ-45 ports that negotiate 100 Mbps, 1GbE, or 10GbE over copper. This is the module to add copper 10GBASE-T server ports to a fiber EX4550-32F, or more copper ports to an EX4550-32T.

EX4550-EM-8XSFP

Eight ports that accept SFP or SFP+ transceivers in any combination of 1GbE and 10GbE.

EX4550-EM-2QSFP

Two 40GbE QSFP+ ports, typically used for uplinks to a 40GbE core or for high-bandwidth links between aggregation switches.

EX4550-VC1-128G

Rather than adding Ethernet ports, this module adds two dedicated Virtual Chassis ports (128 Gbps total) so the EX4550 can be stacked with other EX4550s, or in a mixed Virtual Chassis with EX4200 and EX4500 members. Per Juniper’s EX4550 hardware guide, any combination of these modules can be installed, one per slot, so an EX4550 running the Virtual Chassis module has room for only one Ethernet expansion module.

Modules Available for EX4600 Juniper Switches

The EX4600 is the newest platform in this guide: a 1U aggregation and campus-core switch with 24 fixed 1GbE/10GbE SFP/SFP+ ports, 4 fixed 40GbE QSFP+ ports, and two front-panel expansion slots. Juniper announced end of life for the EX4600 on June 29, 2026, with a last order date of December 29, 2026 and end of support on December 29, 2031, so it will remain supportable by Juniper for several more years and is a good candidate for buying refurbished.

• EX4600-EM-8F – 8-port 1GbE/10GbE SFP/SFP+ expansion module
• QFX-EM-4Q – 4-port 40GbE QSFP+ expansion module

Both modules are included in the EX4600 end-of-life announcement and share its milestone dates.

EX4600-EM-8F

Eight ports accepting SFP or SFP+ transceivers in any mix. Two of these bring the EX4600 to 40 SFP/SFP+ ports plus the four built-in QSFP+ ports.

QFX-EM-4Q

Four 40GbE QSFP+ ports. The part number carries a QFX prefix because the EX4600 shares its hardware design with the QFX5100-24Q, and this is the same module used in that switch’s expansion slots. With two QFX-EM-4Q modules installed the EX4600 has twelve 40GbE ports.

Current-Generation Successors: EX4400, EX4100, and EX4650

If you are replacing rather than sparing one of the platforms above, Juniper’s current access and aggregation switches are the EX4400 and EX4100 at the access layer and the EX4650 for aggregation. Only the EX4400 continues the uplink-module design covered in this guide.

EX4400 Extension Modules

Per Juniper’s EX4400 hardware documentation, every EX4400 model (EX4400-24T, -24P, -24X, -24MP, -48T, -48P, -48F, -48XP, -48MP, and -48MXP) has a single slot for an optional extension module, and the modules are hot-insertable and hot-removable field-replaceable units. Three modules are offered:

• EX4400-EM-4S – four ports accepting 1GbE SFP or 10GbE SFP+ transceivers (Junos OS 21.1R1 and later)
• EX4400-EM-4Y – four ports accepting 1GbE SFP, 10GbE SFP+, or 25GbE SFP28 transceivers, with MACsec AES-256 support (Junos OS 21.1R1 and later)
• EX4400-EM-1C – one port accepting a 40GbE QSFP+ or 100GbE QSFP28 transceiver, channelizable to 10 or 25 Gbps, with MACsec AES-256 support (Junos OS 23.1R1 and later)

Juniper notes that all three modules are supported on the EX4400-48XP and EX4400-48MXP from Junos OS 24.2R1-S1. Separately from the extension slot, each EX4400 has two rear QSFP28 ports that by default operate as Virtual Chassis ports (each as two logical 50 Gbps VCP interfaces), allowing up to ten EX4400 switches in one Virtual Chassis. In practice the EX4400-EM-4Y is the module most buyers want, since it gives an EX4400 access stack 25GbE uplinks without giving up the Virtual Chassis ports.

EX4650: Fixed Configuration, No Modules

The EX4650-48Y that replaces the EX4550 and EX4600 in the aggregation role is a fixed-configuration 1U switch: 48 ports at 1/10/25GbE (SFP28) and 8 ports at 40/100GbE (QSFP28), with breakout support on the 100GbE ports and no expansion slots. Juniper positions it as a distribution or aggregation switch with Virtual Chassis support for up to four members (Junos OS 20.1R1 and later). If your EX4600 design relied on adding QFX-EM-4Q modules for extra 40GbE ports, note that the EX4650 delivers its uplink density through the eight built-in 100GbE ports instead.

EX Series Module Compatibility Table

BrightStar Systems Is an Independent Reseller of Used Juniper Hardware

BrightStar Systems stocks used Juniper EX Series uplink and expansion modules alongside pre-owned Juniper EX Series switches and the optical transceivers to go in them. Every unit goes through our 9-point testing process and ships with our 1-year in-house warranty for end users. If you are not sure which module your switch accepts, contact us with the switch model number and we will confirm compatibility before you buy. For a broader look at the EX line, see our Juniper QFX vs EX Series comparison.