]> Using IS-IS To Advertise Power Group Membership HPE
USA Jonathan.barth@hpe.com
HPE
USA tony.li@tony.li
HPE
USA vbeeram@hpe.com
HPE
USA ronald.bonica@hpe.com
Routing LSR WG ISIS Many networks have a daily utilization pattern. For example, a network might be busy during the day and less busy at night. If the network is robust, it has enough capacity to satisfy demand during peak hours and excess capacity during non-peak hours. That excess capacity increases energy costs and environmental impact. introduces a Power Conserving Path Placement Strategy (PCPPS). When possible, PCPPS concentrates traffic onto a small set of network resources. When traffic is concentrated onto a small set of network resources, other network resources become idle and can be powered down until they are needed again. This solves the problem of excess capacity during non-peak hours. PCPPS uses information that is distributed by an IGP. This document specifies the IS-IS encoding for that information.
Introduction Many networks have a daily utilization pattern. For example, a network might be busy during the day and less busy at night. If the network is robust, it has enough capacity to satisfy demand during peak hours and excess capacity during non-peak hours. That excess capacity increases energy costs and environmental impact. introduces a Power Conserving Path Placement Strategy (PCPPS). When possible, PCPPS concentrates traffic onto a small set of network resources. When traffic is concentrated onto a small set of network resources, other network resources become idle and can be powered down until they are needed again. This solves the problem of excess capacity during non-peak hours. PCPPS uses information that is distributed by an IGP. This document specifies the IS-IS encoding for that information.
Conventions and Definitions The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP14 when, and only when, they appear in all capitals, as shown here.
Terminology The following terms are used as defined in :
  • Power Group
  • Sleep Status, AWAKE and ASLEEP
  • Power Savings Potential (PSP)
Link State Database (LSDB) Elements
The Power Group TLV The Power Group TLV is a top level TLV. If a Power Group is sleep-capable, it is advertised by IS-IS and appears in the LSDB. Otherwise, it is not advertised by IS-IS and it does not appear in the LSDB.
Power Group TLV 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 Type Length Power Group Identifier Power Group Identifier (cont ) PSP PSP (cont ) Parent Identifier Parent Identifier cont
Where:
  • Type: 1 octet, value TBD1
  • Length: 1 octet, unsigned integer. Value 12.
  • Power Group Identifier: 4 octets, selector. MUST NOT be equal to 0.
  • PSP: 4 octets, unsigned integer. The Power Group's PSP, in milliwatts.
  • Parent Identifier: 4 octets, selector.
The Power Group Identifier has node-local significance. If the Parent Identifier is equal to 0, the Power Group has no parent (i.e., it is the root of a Power Group hierarchy). Otherwise, the Parent Identifier MUST NOT be set to 0.
The Sleeping Adjacencies TLV The Sleeping Adjacencies TLV is a top level TLV. An adjacency is sleeping if it satisfies the following criteria:
  • It has been UP in the past
  • It is not currently UP
  • All of the interfaces that supports it are ASLEEP.
The Sleeping Adjacencies TLV can include TLVs 22, 23, 141, 222 and 223.
Sleeping Adjacencies TLV 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 Type Length Sleeping Adjacencies / . / . / .
Where:
  • Type: 1 octet, value TBD2
  • Length: 1 octet, unsigned integer. The length of the TLV, measured in octets, not including the type and length fields.
  • Sleeping Adjacencies: A list of adjacency TLVs of type 22, 23, 141, 222 and 223.
Interface Extensions
The Power Group Member Sub-TLV This sub-TLV is found in TLVs for advertising neighbor information. This sub-TLV advertises a Power Group to which the interface belongs. Because a LAG interface can belong to many Power Groups, many instances of this sub-TLV may be advertised.
Power Group Member Sub-TLV 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 Type Length Power Group Identifier Power Group Identifier (cont )
Where:
  • Type: 1 octet, value TBD3
  • Length: 1 octet, unsigned integer. Value 4.
  • Power Group Identifier: 4 octets, selector.
The Interface PSP Sub-TLV This sub-TLV is found in TLVs for advertising neighbor information. This sub-TLV advertises an interface's PSP.
Interface Power Sub-TLV 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 Type Length PSP PSP (cont )
Where:
  • Type: 1 octet, value TBD4
  • Length: 1 octet, unsigned integer. Value 4
  • PSP: 4 octets, unsigned integer. The interface's PSP, in milliwatts.
Unidirectional Sleeping Bandwidth Sub-TLV This sub-TLV is found in TLVs for advertising neighbor information. This sub-TLV advertises the sleeping bandwidth. The sleeping bandwidth advertised by this sub-TLV MUST be the sleeping bandwidth from the system originating the Link State Advertisement (LSA) to its neighbor.
Unidirectional Sleeping Bandwidth Sub-TLV 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 Type Length Sleeping Bandwidth Sleeping Bandwidth
Where:
  • Type: 1 octet, value TBD5
  • Length: 1 octet, unsigned integer. Value 4.
  • Sleeping Bandwidth: 4 octets, IEEE floating-point format measured in bytes per second.
The Sleeping bandwidth field carries the sleeping bandwidth on a link, forwarding adjacency [RFC4206], or bundled link. For a link or forwarding adjacency, sleeping bandwidth is defined as the maximum bandwidth [RFC5305] minus the bandwidth currently allocated to RSVP-TE label switched paths that was transitioned to power-sleep. For a bundled link, sleeping bandwidth is defined to be the sum of the component link sleeping bandwidths.
The Power-Sleep Capable Bit This is a bit in the Link Attribute Sub-TLV (19). Presence of this bit indicates that the link may be put into power-sleep mode. The position of this bit is TBD5.
Security Considerations TBD
IANA Considerations IANA is requested to add the following entries to the IS-IS Top-Level TLV Codepoints registry (https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-codepoints.xhtml#tlv-codepoints): IS-IS Top-Level TLV Codepoints
Value Name IIH LSP SNP Purge MP Status Reference
TBD1 Power Group N Y N N N This document
TBD2 Sleeping Adjacencies N Y N N N This document
IANA is also requested to add the following entries to the IS-IS Sub-TLVs for TLVs Advertising Neighbor Information registry (https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-codepoints.xhtml#isis-tlv-codepoints-advertising-neighbor-information): IS-IS Sub-TLVs for TLVs Advertising Neighbor Information
Type Description 22 23 25 141 222 223 MP Reference
TBD3 Power Group Member Y Y Y(s) Y Y Y N This document
TBD4 Interface PSP Y Y Y(s) Y Y Y N This document
TBD5 Unidirectional Sleeping Bandwith Y Y Y(s) Y Y Y N This document
IANA is also requested to add the following entry to the IS-IS Neighbor Link-Attribute Bit Values registry (https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-codepoints.xhtml#isis-tlv-codepoints-19of22): IS-IS Neighbor Link-Attribute Bit Values
Value Name L2BM Reference
TBD5 Power-Sleep Capable N This document
Acknowledgements Thanks to Les Ginsberg for his review and comments.
Normative References Key words for use in RFCs to Indicate Requirement Levels In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings. A Power Conserving Path Placement Strategy (PCPPS) HPE HPE HPE HPE A robust network has enough capacity to satisfy demand during peak hours. It has extra capacity to ensure fault-tolerance. Many networks have a daily utilization pattern. For example, a network might be busy during the day and less busy at night. These networks have sufficient capacity during peak hours, and excess capacity during non-peak hours. Excess capacity increases energy costs and environmental impact. This document introduces a Power Conserving Path Placement Strategy (PCPPS). When possible, PCPPS concentrates traffic onto a small set of network resources. When traffic is concentrated onto a small set of network resources, other network resources become idle and can be powered down until they are needed again. This solves the problem of excess capacity during non-peak hours.