| Internet-Draft | DLEP Radio Band Extension | October 2025 |
| Rogge | Expires 23 April 2026 | [Page] |
This document defines an extension to the Dynamic Link Exchange Protocol (DLEP) to provide information about frequency bands used by the radio.¶
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The dynamic Link Exchange Protocol (DLEP) is defined in [RFC8175]. It provides the exchange of link-related control information between DLEP peers. DLEP peers are consist of a modem and a router. DLEP defines a base set of mechanisms as well as support for possible extensions. This document defines one such extension to provide information about the frequency bands used by the radio.¶
In many IETF documents, several words, when they are in all capitals as shown below, are used to signify the requirements in the specification. These capitalized words can bring significant clarity and consistency to documents because their meanings are well defined. This document defines how those words are interpreted in IETF documents when the words are in all capitals.¶
Authors who follow these guidelines should incorporate this phrase near the beginning of their document:¶
The use of the Radio Band Extension SHOULD be configurable. To indicate that the Radio Band Extension is to be used, an implementation MUST include the Radio Band Extension Type Value in the Extensions Supported Data Item. The Extensions Supported Data Item is sent and processed according to [RFC8175].¶
The Radio Band Extension Type Value is described in Section 5.1.¶
Radio Band Data Item contains information which radio frequency resources are being used. These values are usually interface specific and static during the DLEP session.¶
The Radio Band Data Item can be used multiple times to represent multiple radio bands.¶
The Item can be used in a neighbor specific message if the radio uses dedicated subcarriers to talk to neighbors.¶
Frequency selection is often controlled by the radio configuration. By giving the radio a standardized way to transmit its selected frequency configuration the router can aggregate multiple radios settings into a common information page, can do some basic checking for configuration mistakes by comparing known radio group configuration with their frequency by radio (if the routers have a second communication channel) or forward the data to an upper layer for visualization.¶
The information in this Item gives the router an easy way to calculate the spectral efficiency of a radio link, how much bandwidth is used for the current data-rate reported by DLEP. This can be integrated into the routing metric to focus traffic on links that use the spectrum efficiently.¶
The Item can also be used as an interface to a cognitive radio controller on the router, analyzing the correlation of transmission disruptions with the frequency bands and could (together with the Request Link Characteristics message) be used to change the frequency of the radio in a standardized way.¶
Both values in the TLV (Carrier Frequency and Bandwidth) are 64 bit unsigned integers.¶
The format of the Radio Band Data Item is:¶
0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Data Item Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Carrier Frequency + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Bandwidth + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flags | +-+-+-+-+-+-+-+-+
The Flags field is defined as:¶
0 1 2 3 4 5 6 7 +-+-+-+-+-+-+-+-+ | Reserved |U|D| +-+-+-+-+-+-+-+-+
The extension introduces a new Data Item for DLEP. The extension does not inherently introduce any additional vulnerabilities above those documented in [RFC8175]. The approach taken to security in that document applies equally when running the extension defined in this document.¶
As described below, IANA has assigned two values per this document. Both assignments are to registries defined by [RFC8175].¶
IANA has assigned the following value in the "Extension Type Values" registry within the "Dynamic Link Exchange Protocol (DLEP) Parameters" registry. The new value is in the range with the "Specification Required" [RFC8126] policy:¶
| Code | Description | Reference |
| TBD2 | Radio Band | This document |
IANA has assigned the following value in the "Data Item Type Values" registry within the "Dynamic Link Exchange Protocol (DLEP) Parameters" registry. The new value is in the range with the "Specification Required" [RFC8126] policy:¶
| Type Code | Description | Reference |
| TBD1 | Radio Band | This document |