Dish Network and AWS teams have just published a public reference architecture [1] on the Dish 5G buildout on AWS. As this is a project my team is involved in, I thought it would be a good diversion from architecture posts to discuss key aspects – the main business case & the architecture principles in this post.
The Business Case
In 2021, DISH and AWS announced a strategic partnership to run DISH’s 5G network on the AWS Cloud.
DISH Network Corporation (DISH, an acronym for DIgital Sky Highway)is an American television provider and the owner of the direct-broadcast satellite provider Dish, commonly known as Dish Network, and the over-the-top IPTV service, Sling TV. Additionally, Dish also offers mobile wireless service, Dish Wireless. On July 1, 2020, Dish acquired prepaid service Boost Mobile and intends to add postpaid service as well in the future. Based out of unincorporated Douglas County, Colorado the company has approximately 16,000 employees. (source – Wikipedia)
DISH Network is deploying the first stand-alone, cloud-native, autonomous 5G network. The company envisions a complete cloud-native 5G network with all its functions, except minimal components of the Radio Access Network (RAN), running in the cloud with fully automated network deployment and operations. In a telecom industry first, DISH will leverage AWS infrastructure and services to build a cloud-based, 5G Open Radio Access Network (O-RAN) that delivers consistent, cost-effective performance from core to the edge. DISH announces Las Vegas will be the first live city in nationwide network deployment. DISH will use AWS Outposts and AWS Local Zones to build its network in the cloud, enabling customers to apply the breadth and depth of AWS capabilities to innovate low-latency 5G applications and services for a wide range of industries. [2]
The Architecture Principles
To achieve DISH’s ambitious 5G rollout target, the company’s architecture team partnered with AWS to design a scalable, automated platform to run its 5G functions. As an industry first and a groundbreaking deployment, the following guidelines were used in architecting the new platform:
- Maximize the use of cloud infrastructure and services.
- Enable the use of 5G components for services in multiple target environments (Dev/Test/Production/Enterprise) with full automation.
- Maximize the use of native automation constructs provided by AWS instead of building overlay automation.
- Maintain the flexibility to use a mix of cloud native APIs as well as existing telecom protocols.
Datacenter Design
Illustration – DISH Datacenter Architecture design [1]
The architecture of DISH’s 5G network leverages the distributed nature of 5G cloud-native network functions and AWS Cloud flexibility, which optimizes the placement of 5G network functions for optimal performance based on latency, throughput and processing requirements. Through this design, DISH aims to provide nationwide 5G coverage.
DISH’s network design utilizes a logical hierarchical architecture consisting of National Data Centers (NDCs), Regional Data Centers (RDCs) and Breakout Edge Data Centers (BEDCs) (above figure) to accommodate the distributed nature of 5G functions and the varying requirements for service layer integration. BEDCs are deployed in AWS Local Zones hosting 5G NFs that have strict latency budgets. They are connected with DISH’s Passthrough Edge Data Centers (PEDC), which serve as an aggregation point for all Local Data Centers (LDCs) and cell sites in a particular market. BEDCs also provide internet peering for general 5G data service and enterprise customer-specific private network service.
DISH is pioneering the deployment of a 5G network using O-RAN standards in the United States. An O-RAN network consists of an RU (Radio Unit), which is deployed on towers and a DU (Distributed Unit), which controls the RU. These units interface with the Centralized Unit (CU), which is hosted in the BEDC at the Local Zone. These combined pieces provide a full RAN solution that handles all radio level control and subscriber data traffic.
Colocated in the BEDC is the User Plane Function (Data Network Name (DNN) = Internet), which anchors user data sessions and routes to the internet. The BEDCs leverage local internet access available in AWS Local Zones, which allows for a better user experience while optimizing network traffic utilization. This type of edge capability also enables DISH enterprise customers and end-users (gamers, streaming media and other applications) to take full advantage of 5G speeds with minimal latency. DISH has access to 16 Local Zones across the U.S. and is continuing to expand. For latest information about Local Zones, visit the AWS Local Zone Page.
RDCs are hosted in the AWS Region across multiple availability zones. They host 5G subscribers’ signaling processes such as authentication and session management as well as voice for 5G subscribers. These workloads can operate with relatively high latencies, which allows for a centralized deployment throughout a region, resulting in cost efficiency and resiliency. For high availability, three RDCs are deployed in a region, each in a separate Availability Zone (AZ) to ensure application resiliency and high availability. An AZ is one or more discrete data centers with redundant power, networking and connectivity in an AWS Region. All AZs in an AWS Region are interconnected with high-bandwidth and low-latency networking over a fully redundant, dedicated metro fiber, which provides high-throughput, low-latency networking between AZs. CNFs deployed in the RDC utilizes an AWS high-speed backbone to failover between AZs for application resiliency. CNFs like AMF and SMF, which are deployed in RDC, continue to be accessible from the BEDC in the Local Zone in case of an AZ failure. They serve as the backup CNF in the neighboring AZ and would take over and service the requests from the BEDC.
Conclusion
The next blog will cover the network architecture of this real-world deployment.
References
[1] Telco Meets AWS Cloud: Deploying DISH’s 5G Network in AWS Cloud https://aws.amazon.com/blogs/industries/telco-meets-aws-cloud-deploying-dishs-5g-network-in-aws-cloud/
[2] DISH Network on Wikipedia
https://en.wikipedia.org/wiki/Dish_Network