draft-ietf-bmwg-fib-term-03.txt   rfc3222.txt 
Benchmarking Methodology Working Group G. Trotter Network Working Group G. Trotter
Internet Draft Agilent Technologies Request for Comments: 3222 Agilent Technologies
Document: draft-ietf-bmwg-fib-term-03.txt September 2001 Category: Informational December 2001
Category: Informational
Terminology for Forwarding Information Base (FIB) based Router Terminology for Forwarding Information Base (FIB) based Router
Performance Performance
Status of this Memo Status of this Memo
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Abstract Abstract
The forwarding performance of an IP router may be dependent upon or This document describes the terms to be used in a methodology that
may be linked to the composition and size of the forwarding determines the IP packet forwarding performance of IP routers as a
information base installed within a router. This document describes function of the forwarding information base installed within a
the terms to be used in a methodology that determines the IP packet router. The forwarding performance of an IP router may be dependent
forwarding performance of IP routers as a function of the forwarding upon or may be linked to the composition and size of the forwarding
information base installed within a router. information base installed within a router.
Table of Contents Table of Contents
1. Introduction....................................................2 1. Introduction....................................................2
2. Overview........................................................2 2. Overview........................................................ 3
3. Existing Definitions............................................3 3. Existing Definitions............................................3
4. Definition Format...............................................3 4. Definition Format...............................................3
5. Definitions - parameters........................................3 5. Definitions - parameters........................................ 4
5.1 Network Prefix.................................................3 5.1 Network Prefix................................................. 4
5.2 Network Prefix Length..........................................4 5.2 Network Prefix Length..........................................4
5.3 Forwarding Information Base (FIB)..............................4 5.3 Forwarding Information Base (FIB).............................. 5
5.4 Forwarding Information Base Entry..............................5 5.4 Forwarding Information Base Entry.............................. 6
5.5 Forwarding Information Base Size...............................5 5.5 Forwarding Information Base Size............................... 6
5.6 Longest Length Prefix Match Algorithm..........................6 5.6 Longest Length Prefix Match Algorithm.......................... 7
5.7 Forwarding Information Base Prefix Distribution................6 5.7 Forwarding Information Base Prefix Distribution................ 7
5.8 Per-Interface or Per-Card Forwarding Information Base..........7 5.8 Per-Interface or Per-Card Forwarding Information Base.......... 8
Terminology for FIB based Router Performance Sept., 2001 5.9 Per-Interface Forwarding Information Base Cache................ 9
5.10 Route Aggregation............................................ 10
5.9 Per-Interface Forwarding Information Base Cache................8 6. Definitions - metrics.......................................... 10
5.10 Route Aggregation.............................................9 6.1 Maximum Forwarding Information Base Size...................... 11
6. Definitions - metrics...........................................9 6.2 Forwarding Information Base Learning Time..................... 11
6.1 Maximum Forwarding Information Base Size.......................9 6.3 Forwarding Information Base-dependent Throughput.............. 12
6.2 Forwarding Information Base Learning Time.....................10 6.4 Forwarding Information Base-dependent Latency................. 12
6.3 Forwarding Information Base-dependent Throughput..............11 6.5 Forwarding Information Base-dependent Frame Loss Rate......... 13
6.4 Forwarding Information Base-dependent Latency.................11 7. Security Considerations........................................ 13
6.5 Forwarding Information Base-dependent Frame Loss Rate.........11 8. References..................................................... 13
7. Security Considerations........................................12 9. Author's Address............................................... 14
8. References.....................................................12 10. Full Copyright Statement...................................... 15
9. Acknowledgments................................................12
10. Author's Addresses............................................12
1. Introduction 1. Introduction
This document defines terms that are to be used in a methodology This document defines terms that are to be used in a methodology that
that determines the IP packet forwarding performance of IP routers determines the IP packet forwarding performance of IP routers as a
as a function of the forwarding information base installed within function of the forwarding information base installed within the
the router. router.
This document is restricted to IPv4 routers.
The objective of this methodology is to evaluate the performance The objective of this methodology is to evaluate the performance
levels of IP routers as forwarding information bases continue to levels of IP routers as forwarding information bases continue to grow
grow in size and complexity of structure. in size and complexity of structure.
This methodology utilizes the packet forwarding performance This methodology utilizes the packet forwarding performance
measurements described in [2]; reference will also be made to the measurements described in [2]; reference will also be made to the
associated terminology document [3] for these terms. associated terminology document [3] for these terms.
2. Overview 2. Overview
In order to measure the forwarding information base-based router In order to measure the forwarding information base-based router
performance, different forwarding information bases (5.3) are performance, different forwarding information bases (5.3) are
installed in the router. The two key elements describing the FIB installed in the router. The two key elements describing the FIB are
are the FIB size (5.5) and FIB prefix distribution (5.6). The the FIB size (5.5) and FIB prefix distribution (5.7). The forwarding
forwarding performance of a router may be dependent upon these two performance of a router may be dependent upon these two primary
primary factors, particularly if FIB prefix distributions tend factors, particularly if FIB prefix distributions tend towards longer
towards longer network prefixes (3). The FIB-dependent throughput, network prefixes (5.1). The FIB-dependent throughput, latency and
latency and frame loss rate (6.3, 6.4, 6.5), measured with fully frame loss rate (6.3, 6.4, 6.5), measured with fully meshed traffic
meshed traffic flows [2], will reflect the change in performance of flows [2], will reflect the change in performance of the router.
the router. Tests may need to be performed up to the maximum FIB Tests may need to be performed up to the maximum FIB size (6.1).
size (6.1).
When configuring the router for these measurements, the routes need When configuring the router for these measurements, the routes need
to be manually entered into the router, or advertised via a routing to be manually entered into the router, or advertised via a routing
protocol. It may take some period of time (the FIB learning time protocol. It may take some period of time (the FIB learning time
(6.2)) before the router learns all the routes. (6.2)) before the router learns all the routes.
When routes are advertised into the router, the routes should be When routes are advertised into the router, the routes should be
advertised in such a way so that route aggregation (5.10) does not advertised in such a way so that route aggregation (5.10) does not
Terminology for FIB based Router Performance Sept., 2001
occur. Also, the effect of a per-interface FIB cache (5.9) needs to occur. Also, the effect of a per-interface FIB cache (5.9) needs to
be taken into account. be taken into account.
3. Existing Definitions 3. Existing Definitions
[3] should be consulted before attempting to make use of this [3] should be consulted before attempting to make use of this
document. [2] contains discussions of a number of terms relevant to document. [2] contains discussions of a number of terms relevant to
the benchmarking of network interconnect devices and should also be the benchmarking of network interconnect devices and should also be
consulted. consulted.
skipping to change at page 3, line 31 skipping to change at page 3, line 50
X.x Term to be defined. (e.g., Latency) X.x Term to be defined. (e.g., Latency)
Definition: Definition:
The specific definition for the term. The specific definition for the term.
Discussion: Discussion:
A brief discussion about the term, it's application and any A brief discussion about the term, it's application and any
restrictions on measurement procedures. restrictions on measurement procedures.
Measurement units: Measurement units:
The units used to report measurements of this term, if The units used to report measurements of this term, if applicable.
applicable.
Issues: Issues:
List of issues or conditions that effect this term. List of issues or conditions that effect this term.
See Also: See Also:
List of other terms that are relevant to the discussion of List of other terms that are relevant to the discussion of this
this term. term.
5. Definitions - parameters 5. Definitions - parameters
This section defines parameters that would dictate the execution of This section defines parameters that would dictate the execution of
methodology to determine the FIB based forwarding performance of a methodology to determine the FIB based forwarding performance of a
router. router.
5.1 Network Prefix 5.1 Network Prefix
Definition: Definition:
"A network prefix is . . . a contiguous set of bits at the more
significant end of the address that defines a set of systems; host
numbers select among those systems."
"A network prefix is . . . a contiguous set of bits at the (This definition is taken directly from section 2.2.5.2,
more significant end of the address that defines a set of "Classless Inter Domain Routing (CIDR)", in [4].)
systems; host numbers select among those systems."
(This definition is taken directly from section 2.2.5,
"Addressing Architecture", in [4].)
Discussion: Discussion:
In the CIDR context, the network prefix is the network component
Terminology for FIB based Router Performance Sept., 2001 of an IP address. A common alternative to using a bitwise mask to
communicate this component is the use of "slash (/) notation."
In the CIDR context, the network prefix is the network Slash notation binds the notion of network prefix length (see 5.2)
component of an IP address. A common alternative to using a in bits to an IP address. E.g., 141.184.128.0/17 indicates the
bitwise mask to communicate this component is the use of network component of this IPv4 address is 17 bits wide.
"slash (/) notation." Slash notation binds the notion of
network prefix length (see 5.2) in bits to an IP address.
E.g., 141.184.128.0/17 indicates the network component of
this IPv4 address is 17 bits wide.
Measurement units: Measurement units:
<n/a> <n/a>
Issues: Issues:
See Also: See Also:
Network Prefix Length (5.2) Network Prefix Length (5.2)
5.2 Network Prefix Length 5.2 Network Prefix Length
Definition: Definition:
The number of bits used to define the network prefix. The number of bits used to define the network prefix. Network
Network prefixes, using CIDR terminology, are typically prefixes, using CIDR terminology, are typically referred to as
referred to as 15.35.128.0 /17, indicating that the network 15.35.128.0 /17, indicating that the network prefix is 17 bits
prefix is 17 bits long. long.
Discussion: Discussion:
When referring to groups of addresses, the network prefix When referring to groups of addresses, the network prefix length
length is often used as a means of describing groups of is often used as a means of describing groups of addresses as an
addresses as an equivalence class. For example, 100 /16 equivalence class. For example, 100 /16 addresses refers to 100
addresses refers to 100 addresses whose network prefix length addresses whose network prefix length is 16 bits.
is 16 bits.
Measurement units: Measurement units:
bits bits
Issues: Issues:
See Also: See Also:
network prefix (5.1) network prefix (5.1)
forwarding information base prefix distribution (5.6) forwarding information base prefix distribution (5.7)
5.3 Forwarding Information Base (FIB) 5.3 Forwarding Information Base (FIB)
Definition: Definition:
As according to the definition in [4]: As according to the definition in Appendix B of [4]:
"The table containing the information necessary to forward IP "The table containing the information necessary to forward IP
Datagrams, in this document, is called the Forwarding Datagrams, in this document, is called the Forwarding Information
Information Base. At minimum, this contains the interface Base. At minimum, this contains the interface identifier and next
identifier and next hop information for each reachable hop information for each reachable destination network prefix."
destination network prefix."
Discussion: Discussion:
Terminology for FIB based Router Performance Sept., 2001
The forwarding information base describes a database indexing The forwarding information base describes a database indexing
network prefixes versus router port identifiers. network prefixes versus router port identifiers.
A forwarding information base consists of [FIB size (6.1)] A forwarding information base consists of [FIB size (5.5)] FIB
FIB entries (5.4). entries (5.4).
The forwarding information base is distinct from the "routing The forwarding information base is distinct from the "routing
table" (or, the Routing Information Base), which holds all table" (or, the Routing Information Base), which holds all routing
routing information received from routing peers. information received from routing peers.
The forwarding information base contains unique paths only The forwarding information base contains unique paths only (i.e.
(i.e. does not contain secondary paths). does not contain secondary paths).
Measurement units: Measurement units:
<none> <none>
Issues: Issues:
See Also: See Also:
forwarding information base entry (5.4) forwarding information base entry (5.4)
forwarding information base size (5.5) forwarding information base size (5.5)
forwarding information base prefix distribution (5.6) forwarding information base prefix distribution (5.7)
maximum forwarding information base size (6.1) maximum forwarding information base size (6.1)
5.4 Forwarding Information Base Entry 5.4 Forwarding Information Base Entry
Definition: Definition:
A single entry within a forwarding information base. This A single entry within a forwarding information base. This entry
entry consists of the minimum amount of information necessary consists of the minimum amount of information necessary to make a
to make a forwarding decision on a particular packet. The forwarding decision on a particular packet. The typical
typical components within a forwarding information base entry components within a forwarding information base entry are a
are a network prefix, a router port identifier and next hop network prefix, a router port identifier and next hop information.
information. This is an entry that the router can and does This is an entry that the router can and does use to forward
use to forward packets. packets.
Discussion: Discussion:
See (5.3). See (5.3).
Measurement units: Measurement units:
<n/a> <n/a>
Issues: Issues:
See Also: See Also:
forwarding information base (5.3) forwarding information base (5.3)
forwarding information base size (5.5) forwarding information base size (5.5)
forwarding information base prefix distribution (5.6) forwarding information base prefix distribution (5.7)
maximum forwarding information base size (6.1) maximum forwarding information base size (6.1)
5.5 Forwarding Information Base Size 5.5 Forwarding Information Base Size
Definition: Definition:
Refers to the number of forwarding information base entries within
Terminology for FIB based Router Performance Sept., 2001 a forwarding information base.
Refers to the number of forwarding information base entries
within a forwarding information base.
Discussion: Discussion:
The number of entries within a forwarding information base is The number of entries within a forwarding information base is one
one of the key elements that may influence the forwarding of the key elements that may influence the forwarding performance
performance of a router. Generally, the more entries within of a router. Generally, the more entries within the forwarding
the forwarding information base, the longer it could take to information base, the longer it could take to find the longest
find the longest matching network prefix within the matching network prefix within the forwarding information base.
forwarding information base.
Measurement units: Measurement units:
Number of routes Number of routes
Issues: Issues:
See Also: See Also:
forwarding information base (5.3) forwarding information base (5.3)
forwarding information base entry (5.4) forwarding information base entry (5.4)
forwarding information base prefix distribution (5.6) forwarding information base prefix distribution (5.7)
maximum forwarding information base size (6.1) maximum forwarding information base size (6.1)
5.6 Longest Length Prefix Match Algorithm 5.6 Longest Length Prefix Match Algorithm
Definition: Definition:
An algorithm that a router uses to quickly match destination An algorithm that a router uses to quickly match destination
addresses within received IP packets to exit interfaces on addresses within received IP packets to exit interfaces on the
the router. router.
Discussion: Discussion:
Measurement Units: Measurement Units:
<none> <none>
Issues: Issues:
See Also: See Also:
5.7 Forwarding Information Base Prefix Distribution 5.7 Forwarding Information Base Prefix Distribution
Definition: Definition:
The distribution of network prefix lengths within the The distribution of network prefix lengths within the forwarding
forwarding information base. information base.
Discussion: Discussion:
Network prefixes within the forwarding information base could Network prefixes within the forwarding information base could be
be all of a single network prefix length, but, more all of a single network prefix length, but, more realistically,
realistically, the network prefix lengths will be distributed the network prefix lengths will be distributed across some range.
across some range.
Individual performance measurements will be made against FIBs Individual performance measurements will be made against FIBs
populated with the same network prefix length, as well as populated with the same network prefix length, as well as against
Terminology for FIB based Router Performance Sept., 2001 FIBs with some distribution of network prefix lengths.
against FIBs with some distribution of network prefix
lengths.
The distribution of network prefix lengths may have an impact The distribution of network prefix lengths may have an impact on
on the forwarding performance of a router. The longer the the forwarding performance of a router. The longer the network
network prefix length, the longer it will take for a router prefix length, the longer it will take for a router to perform the
to perform the longest length prefix match algorithm, and longest length prefix match algorithm, and potentially the lower
potentially the lower the performance of the router. the performance of the router.
Measurement units: Measurement units:
The forwarding information base prefix distribution is The forwarding information base prefix distribution is expressed
expressed by a list of network prefix lengths and the by a list of network prefix lengths and the percentage of entries
percentage of entries within the forwarding information base within the forwarding information base with a particular network
with a particular network prefix length. For example, a prefix length. For example, a forwarding information base prefix
forwarding information base prefix distribution is distribution is represented as:
represented as:
{[/16, 100], [/20, 360], [/24, 540]} {[/16, 100], [/20, 360], [/24, 540]}
This indicates that 100 of the entries within the forwarding This indicates that 100 of the entries within the forwarding
information base have a 16 bit network prefix length, 360 information base have a 16 bit network prefix length, 360 have a
have a 20 bit network prefix length, and 540 have a 24 bit 20 bit network prefix length, and 540 have a 24 bit network prefix
network prefix length. length.
Issues: Issues:
See Also: See Also:
forwarding information base (5.3) forwarding information base (5.3)
forwarding information base entry (5.4) forwarding information base entry (5.4)
forwarding information base size (5.5) forwarding information base size (5.5)
maximum forwarding information base size (6.1) maximum forwarding information base size (6.1)
5.8 Per-Interface or Per-Card Forwarding Information Base 5.8 Per-Interface or Per-Card Forwarding Information Base
Definition: Definition:
A complete copy of the forwarding information base, installed A complete copy of the forwarding information base, installed on a
on a router's card or individual physical interface to speed router's card or individual physical interface to speed the
the destination address to network prefix lookup process. destination address to network prefix lookup process.
Discussion: Discussion:
Router manufacturers have developed many optimizations for Router manufacturers have developed many optimizations for
routers, of which one optimization is to copy the forwarding routers, of which one optimization is to copy the forwarding
information base to every interface or interface card on the information base to every interface or interface card on the
router. By doing this, destination address / network prefix router. By doing this, destination address / network prefix
lookups can be performed on the interface or card, unloading lookups can be performed on the interface or card, unloading a
a router's CPU. router's CPU.
Measurement units: Measurement units:
<n/a> <n/a>
Issues: Issues:
See Also: See Also:
Terminology for FIB based Router Performance Sept., 2001
forwarding information base (5.3) forwarding information base (5.3)
per-interface forwarding information base cache (5.9) per-interface forwarding information base cache (5.9)
5.9 Per-Interface Forwarding Information Base Cache 5.9 Per-Interface Forwarding Information Base Cache
Definition: Definition:
A subset of a forwarding information base, installed on a A subset of a forwarding information base, installed on a router's
router's interface card to speed the destination address / interface card to speed the destination address / network prefix
network prefix lookup process. lookup process.
Discussion: Discussion:
Prior to installing a complete copy of the forwarding Prior to installing a complete copy of the forwarding information
information base on each interface of a router, a popular base on each interface of a router, a popular technique for
technique for speeding destination address lookups is to speeding destination address lookups is to install a cache of
install a cache of frequently used routes on a router's frequently used routes on a router's interface.
interface.
The most frequently used routes are placed in the forwarding The most frequently used routes are placed in the forwarding
information base cache. IP packets whose destination address information base cache. IP packets whose destination address does
does not match a network prefix within the per-interface not match a network prefix within the per-interface forwarding
forwarding information base cache are forwarded to a router's information base cache are forwarded to a router's central
central processor for lookup in the complete forwarding processor for lookup in the complete forwarding information base.
information base.
The implication for benchmarking the performance of a router The implication for benchmarking the performance of a router as a
as a function of the forwarding information base is function of the forwarding information base is significant. IP
significant. IP packets whose destination address matches an packets whose destination address matches an entry within the
entry within the per-interface forwarding information base per-interface forwarding information base cache could be forwarded
cache could be forwarded more quickly than packets whose more quickly than packets whose destination address does not match
destination address does not match an entry within the per- an entry within the per-interface forwarding information base
interface forwarding information base cache. cache.
To create useful benchmarks, the role of a per-interface To create useful benchmarks, the role of a per-interface
forwarding cache needs to be considered. The nature of forwarding cache needs to be considered. The nature of
benchmarking tests to measure the impact of the forwarding benchmarking tests to measure the impact of the forwarding
performance of a router requires that the destination performance of a router requires that the destination addresses
addresses within IP packets transmitted into the router be within IP packets transmitted into the router be distributed
distributed amongst the total set of network prefixes amongst the total set of network prefixes advertised into the
advertised into the router. This negates the role of a per- router. This negates the role of a per-interface forwarding
interface forwarding information base cache, but serves to information base cache, but serves to stress the forwarding
stress the forwarding information base-based packet information base-based packet forwarding performance of the
forwarding performance of the router. router.
Measurement units: Measurement units:
<n/a> <n/a>
Issues: Issues:
See Also: See Also:
forwarding information base (5.3) forwarding information base (5.3)
per-interface forwarding information base (5.8) per-interface forwarding information base (5.8)
Terminology for FIB based Router Performance Sept., 2001
5.10 Route Aggregation 5.10 Route Aggregation
Definition: Definition:
The ability of a router to collapse many forwarding The ability of a router to collapse many forwarding information
information base entries into a single entry. base entries into a single entry.
Discussion: Discussion:
A router may aggregate routes in a forwarding information A router may aggregate routes in a forwarding information base
base into a single entry to conserve space. into a single entry to conserve space.
When advertising routes into a router to perform benchmarking When advertising routes into a router to perform benchmarking
tests as a function of the forwarding information base tests as a function of the forwarding information base installed
installed within the router, it is necessary to ensure that a within the router, it is necessary to ensure that a router does
router does not aggregate routes. not aggregate routes.
Thus, when routes are advertised to the router or installed Thus, when routes are advertised to the router or installed
statically, care must be taken to ensure that the router does statically, care must be taken to ensure that the router does not
not aggregate routes. aggregate routes.
For example, if advertising a set of /24 network prefixes For example, if advertising a set of /24 network prefixes into a
into a particular port on the router, 256 consecutive /24 particular port on the router, 256 consecutive /24 routes, sharing
routes, sharing a common leading 16 bits, should not be a common leading 16 bits, should not be advertised on a single
advertised on a single port. If this is done, then the port. If this is done, then the router will install a single
router will install a single entry within the forwarding entry within the forwarding information base indicating that all
information base indicating that all networks matching a networks matching a particular /16 network prefix are accessible
particular /16 network prefix are accessible through one through one particular entry.
particular entry.
Route aggregation on a router can be turned off, but routes Route aggregation on a router can be turned off, but routes should
should still be advertised into the router in such a manner still be advertised into the router in such a manner as to avoid
as to avoid route aggregation. route aggregation.
Measurement units: Measurement units:
<none> <none>
Issues: Issues:
See Also: See Also:
6. Definitions - metrics 6. Definitions - metrics
This section defines the metrics, or results, that would This section defines the metrics, or results, that would
characterized the FIB based forwarding performance of a router. characterized the FIB based forwarding performance of a router.
6.1 Maximum Forwarding Information Base Size 6.1 Maximum Forwarding Information Base Size
Definition: Definition:
The maximum number of forwarding information base entries The maximum number of forwarding information base entries that can
that can be supported within the forwarding information base. be supported within the forwarding information base. The Maximum
The Maximum Forwarding Information Base Size is the size over Forwarding Information Base Size is the size over which all
which all entries can and are used to forward traffic. entries can and are used to forward traffic.
Discussion: Discussion:
It is useful to know the maximum forwarding information base size
for a router as it will be an indicator of the ability of the
router to function within the given application space, and whether
the router will be able to handle projected network growth.
Terminology for FIB based Router Performance Sept., 2001 As a benchmarking value, it is necessary to discover this value so
that performance measurements can be made up to the maximum
It is useful to know the maximum forwarding information base possible forwarding information base size.
size for a router as it will be an indicator of the ability
of the router to function within the given application space,
and whether the router will be able to handle projected
network growth.
As a benchmarking value, it is necessary to discover this
value so that performance measurements can be made up to the
maximum possible forwarding information base size.
Measurement units: Measurement units:
Number of routes Number of routes
Issues: Issues:
Could this value vary with the forwarding information base Could this value vary with the forwarding information base prefix
prefix distribution? distribution?
See Also: See Also:
forwarding information base (5.3) forwarding information base (5.3)
forwarding information base entry (5.4) forwarding information base entry (5.4)
forwarding information base size (5.5) forwarding information base size (5.5)
forwarding information base prefix distribution (5.6) forwarding information base prefix distribution (5.7)
6.2 Forwarding Information Base Learning Time 6.2 Forwarding Information Base Learning Time
Definition: Definition:
The time a router takes to process received routing messages, The time a router takes to process received routing messages, and
and to construct (and, possibly to distribute amongst the to construct (and, possibly to distribute amongst the interface
interface cards in the router) the forwarding information cards in the router) the forwarding information base. This is
base. This is measured from the time at which a router is measured from the time at which a router is presented with the
presented with the first routing message, through to when it first routing message, through to when it can forward packets
can forward packets using any entry in the forwarding using any entry in the forwarding information base.
information base.
Discussion: Discussion:
It takes time for a router to construct its forwarding It takes time for a router to construct its forwarding information
information base. A router needs to process received routing base. A router needs to process received routing packets, build
packets, build the routing information database, select the the routing information database, select the best paths, build the
best paths, build the forwarding information base and then forwarding information base and then possibly distribute the
possibly distribute the forwarding information base or a forwarding information base or a subset thereof to the interface
subset thereof to the interface cards. This entire process cards. This entire process can take several minutes with very
can take several minutes with very large forwarding large forwarding information bases.
information bases.
When performing benchmarking tests that take the forwarding When performing benchmarking tests that take the forwarding
information base into account, time must be allocated for the information base into account, time must be allocated for the
router to process the routing information and to install the router to process the routing information and to install the
complete forwarding information base within itself, before complete forwarding information base within itself, before
performance measurements are made. performance measurements are made.
Measurement units: Measurement units:
Prefixes per second. Prefixes per second.
Terminology for FIB based Router Performance Sept., 2001
Issues: Issues:
See Also: See Also:
forwarding information base (5.3) forwarding information base (5.3)
6.3 Forwarding Information Base-dependent Throughput 6.3 Forwarding Information Base-dependent Throughput
Definition: Definition:
Throughput, as defined in [3], used in a context where the Throughput, as defined in [3], used in a context where the
forwarding information base influences the throughput. forwarding information base influences the throughput.
Discussion: Discussion:
This definition for FIB-dependent throughput is added to This definition for FIB-dependent throughput is added to
distinguish the context of this measurement from that defined distinguish the context of this measurement from that defined in
in [3]. [3].
Measurement units: Measurement units:
See [3]. See [3].
Issues: Issues:
See Also: See Also:
forwarding information base-dependent latency (6.4) forwarding information base-dependent latency (6.4)
forwarding information base-dependent frame loss rate (6.5) forwarding information base-dependent frame loss rate (6.5)
6.4 Forwarding Information Base-dependent Latency 6.4 Forwarding Information Base-dependent Latency
Definition: Definition:
Latency, as defined in [3], used in a context where the Latency, as defined in [3], used in a context where the forwarding
forwarding information base influences the throughput. information base influences the throughput.
Discussion: Discussion:
This definition for FIB-dependent latency is added to This definition for FIB-dependent latency is added to distinguish
distinguish the context of this measurement from that defined the context of this measurement from that defined in [3].
in [3].
Measurement units: Measurement units:
See [3]. See [3].
Issues: Issues:
See Also: See Also:
forwarding information base-dependent throughput (6.3) forwarding information base-dependent throughput (6.3)
forwarding information base-dependent frame loss rate (6.5) forwarding information base-dependent frame loss rate (6.5)
6.5 Forwarding Information Base-dependent Frame Loss Rate 6.5 Forwarding Information Base-dependent Frame Loss Rate
Definition: Definition:
Frame Loss Rate, as defined in [3], used in a context where Frame Loss Rate, as defined in [3], used in a context where the
the forwarding information base influences the throughput. forwarding information base influences the throughput.
Discussion: Discussion:
Terminology for FIB based Router Performance Sept., 2001
This definition for FIB-dependent frame loss rate is added to This definition for FIB-dependent frame loss rate is added to
distinguish the context of this measurement from that defined distinguish the context of this measurement from that defined in
in [3]. [3].
Measurement units: Measurement units:
See [3]. See [3].
Issues: Issues:
See Also: See Also:
forwarding information base-dependent throughput (6.3) forwarding information base-dependent throughput (6.3)
forwarding information base-dependent latency (6.4) forwarding information base-dependent latency (6.4)
7. Security Considerations 7. Security Considerations
As this document is solely for the purpose of providing metric As this document is solely for the purpose of providing metric
methodology and describes neither a protocol nor a protocols methodology and describes neither a protocol nor a protocols
implementation, there are no security considerations associated with implementation, there are no security considerations associated with
this document. this document.
8. References 8. References
1 Bradner, S., "The Internet Standards Process -- Revision 3", BCP [1] Bradner, S., "The Internet Standards Process -- Revision 3", BCP
9, RFC 2026, October 1996. 9, RFC 2026, October 1996.
2 Bradner, S., McQuaid, J., "Benchmarking Methodology for Network
Interconnect Devices", RFC 2544, March 1999
3 Bradner, S., "Benchmarking Terminology for Network
Interconnection Devices", RFC 1242, July 1991
4 Baker, F., "Requirements for IP Version 4 Routers", RFC 1812,
June 1995
9. Acknowledgments [2] Bradner, S. and J. McQuaid, "Benchmarking Methodology for Network
Interconnect Devices", RFC 2544, March 1999.
10. Author's Addresses [3] Bradner, S., "Benchmarking Terminology for Network
Interconnection Devices", RFC 1242, July 1991.
[4] Baker, F., "Requirements for IP Version 4 Routers", RFC 1812,
June 1995.
9. Author's Address
Guy Trotter Guy Trotter
Agilent Technologies (Canada) Inc. Agilent Technologies (Canada) Inc.
#2500 4710 Kingsway #2500 4710 Kingsway
Burnaby, British Columbia Burnaby, British Columbia
Canada Canada
V5H 4M2 V5H 4M2
Phone: +1 604 454 3516 Phone: +1 604 454 3516
Email: Guy_Trotter@agilent.com EMail: Guy_Trotter@agilent.com
Full Copyright Statement 10. Full Copyright Statement
"Copyright (C) The Internet Society (2001). All Rights Reserved. Copyright (C) The Internet Society (2001). All Rights Reserved.
This document and translations of it may be copied and furnished to This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it others, and derivative works that comment on or otherwise explain it
Terminology for FIB based Router Performance July, 2001
or assist in its implementation may be prepared, copied, published or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph kind, provided that the above copyright notice and this paragraph are
are included on all such copies and derivative works. However, this included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for developing Internet standards in which case the procedures for
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English. English.
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Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
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