ACX7024 Deepdive¶
Everything about the new addition to the Cloud-Metro family, the ACX7024. A 1-RU router, with 360Gbps forwarding capacity.
Introduction¶

ACX7024 is 1RU Ethernet-only router with 360Gbps bidirectional forwarding capacity and with Class-C Timing. It is the temperature hardened and support from -40C to +65C.
This router is primarily targeted at the Cell site /Access market but can be used in multiple roles as soon as features and scales are meeting the requirements. It supports Ethernet ports from 1GE to 100GE.
Maximum number of ports supported on ACX7024:
| Port Speed | ACX7024 Ports Details | Total |
|---|---|---|
| 100GE | 4x1 | 4 |
| 50GE | 4x (2x1) | 8 |
| 40GE | 4x1 | 4 |
| 25GE | 24 + 4x (4x1) | 40 |
| 10GE | 24 + 4x (4x1) | 40 |
| 1GE | 24x1 | 24 |
Naming Convention¶
We have a total of 4 SKUs (Stock Keeping Units) available based on Power supply module type and number.
- ACX7024-DC-1PSU: ACX7024 with single DC PSU
- ACX7024-DC-2PSU: ACX7024 with two DC PSUs Redundant PSU]
- ACX7024-AC-1PSU: ACX7024 with single AC PSU
- ACX7024-AC-2PSU: ACX7024 with two AC PSUs [Redundant PSU]
Ports density: 4x 100GE and 24 x 1/10/25GE:
- Port Number 0 to 3 [QSFP+ 40/100G]
- Port Number 4 to 27 [SFP+ 1/10/25/G]
System cooling is AFO (Air Flow Out / Front-to-Back) or Side to side with Baffle. And we have 4 options for power supply: AC or DC, and 1 or 1+1 PSU. The typical power consumption is below 200W.
Based on these parameters, the naming logic for the product itself and the SKU are the following.



Environment standards¶
ACX7024 is the temperature hardened box [-40C to 65C]and is compliant to below Environment standards
- IEEE1613:2013 Smart Grid -- Power Substations
- IEC 61850-3:2013 Telecom equipment in Power station and substation environments
- GR 63 issue 5
- GR 3108- Class 2 Edition 3
Software¶
Oversubscription¶

ACX7024 Ethernet Ports¶
ACX7024 Front Panel view and Port Numbering¶

| Port Number | Optic Type | Supported Port Speed | Default Port Speed |
|---|---|---|---|
| 0 - 3 | QSFP28/QSFP+ | 100G,40G,2x50G,4x25,4x10G | 100G |
| 4 - 27 | SFP/SFP+/SFP28 | 1G,10G,25G | 10G |
ACX7024 Port¶

ACX7024 Rear View¶

Port Configuration and Port Checker Tool¶

Port speed and supported FEC:
| Port Speed | Supported FEC |
|---|---|
| 100GE | FEC91,None |
| 50GE | FEC91,None |
| 40GE | FEC74,None |
| 25GE | FEC91,FEC74,None |
| 10GE | FEC74,None |
Channelized interface configuration: by default et-0/0/2 is with 100G speed, if you want to use this port as 4x25 mode set below command.
Serdes Rate¶
SerDes or serializer/deserializer is an integrated circuit (IC or chip) transceiver that converts parallel data to serial data and vice-versa. With Broadcom Qumran2u, below are the serdes rate for respective port speed. Keep in mind that port speed and Serdes rates are different, the second category is Broadcom internal rates: 10.3125Gbps, 25.7825Gbps, 1.25Gbps...
| SFP Ports 4 - 27 | Q2u SerDes (Gbps) |
|---|---|
| 25GE | 25.78125 |
| 10GE | 10.3125 |
| 1GE | 1.25 |
| QSFP28 Ports 0 - 3 | |
| 100GE | 4x 25.78125 |
| 40GE | 4x10.3125 |
| 2x50GE | 4x25.78125 |
| 4x10GE | 4x10.3125 |
| 4x25GE | 4x25.78125 |
Supported Optics¶
https://apps.juniper.net/hct/product/?prd=ACX7024
Internal Description: Block Diagrams¶
ACX7024 is internally composed of multiple parts. We can summarize them as:
- A Broadcom Qumran2u PFE (BCM88284) with 2GB of GDDR6
- Intel xC3508 CPU (4 cores) with DDR4 memory and SSD storage
- Internal controllers for I2C (inter-integrated circuit), fan control, ...
- PTP FPGA
- TPM 2.0 module (Trusted Platform Module)

In this diagram, we are presenting the SerDes at 50G (instead of 53.125G) and 25G (instead of 25.7875G) for sake of simplicity. The block diagram clearly explains the hardware shared for port 27 and PTP FPGA via mux section.
The different components can be monitored via CLI.
Fan Tray and Power Module Redundancy¶
ACX7024 have a single routing engine. That means we don't support any kind of High-Availability (HA) option at the RE level. Also, In-Service System Upgrade (ISSU) is not supported, nor planned.
The only field replaceable parts on these routers are:
- the Power Supply Modules (2x AC or 2x DC)
AC and DC systems
You notice two PSM on both ends of the router, they can be AC or DC with single PSU or dual. But we can't mix the two categories. With a 1+1 PSM configuration, we have power redundancy: if one fails, the system will raise an alarm but will stay fully operational.
ACX7024 relies on six fixed fans for cooling purposes:
- ACX7024 is designed for front-to-back airflow and side to side with baffle airflow
The system supports single rotor failure and FAN 5+1 redundancy.
PFE Description¶
We invite you to check the articles to learn more about the ASIC selection process and many more details on the packet forwarding ASIC.
-
Building the ACX7000 Series: the PFE: https://juniper.github.io/techposts/building-the-acx7000-series-the-pfe/article
-
Let's Talk About VOQ and DNX Pipeline: https://juniper.github.io/techposts/voq-and-dnx-pipeline/article
The ACX7024 is "Systems on the Chip" (SoC). That means it is based on a single PFE where all parts involved in the forwarding tasks are directly connected. This Qumran (BCM88284) PFE is a deep-buffer ASIC with hybrid packet memory (internal and external). The external buffer is 2x 8Gb (2GB) of GDDR6 memory.
Follow-up articles will come in near future describing some internal key aspects of the PFE like the oversubscription handling etc.
Timing Support¶
- Supports Synchronous Ethernet with enhanced ESMC
- Supports PTP G.8275.1/G.8275.1enh/G.8275.2 Profile
- Meets G.8273.2 T-BC Class C Performance
- Supports 1588 transparent clock along with G.8273.3 T-TC
Note:- Sync-E and PTP Hybrid not supported on 1G ports.
In Conclusion¶
The ACX7024 router is 1-RU, 360Gbps platform, ideally positioned for small cell site and it can be with 1G/10G/25/50GE/40G aggregation. In the next articles, we will continue the description of the ACX7000 portfolio and will dig deeper into the specific features of these products.
Useful links¶
- ACX7024 Data sheet: https://www.juniper.net/us/en/products/routers/acx-series/acx7024-cloud-metro-router-datasheet.html
- Product introduction on YouTube: https://www.youtube.com/watch?v=tzEeTW5JODk
- Building the ACX7100 Series: the PFE: https://juniper.github.io/techposts/building-the-acx7000-series-the-pfe/article
- Let's talk about VOQ and DNX Pipeline: https://juniper.github.io/techposts/voq-and-dnx-pipeline/article
- Hardware guides: https://www.juniper.net/documentation/us/en/hardware/acx7024/index.html
- HCT Link: https://apps.juniper.net/hct/product/?prd=ACX7024
Glossary¶
- AFO: AirFlow Out
- FRS: First Revenue Ship
- I2C: Inter-Integrated Circuit
- PFE: Packet Forwarding Engine
- PSM : Power Supply Module
- PTP: Precision Time Protocol
- SKU: Stock Keeping Unit
- TPM : Trusted Platform Module
- PSU: Power Supply Unit
Acknowledgments¶
Thanks a lot to Ravi Modgekar and Nicolas for document review.