Internet Engineering Task Force (IETF) S. Banks
Request for Comments: 7654 VSS Monitoring
Category: Informational F. Calabria
ISSN: 2070-1721 Cisco Systems
G. Czirjak
R. Machat
Juniper Networks
October 2015
Benchmarking Methodology for In-Service Software Upgrade (ISSU)
Abstract
Modern forwarding devices attempt to minimize any control- and data-
plane disruptions while performing planned software changes by
implementing a technique commonly known as In-Service Software
Upgrade (ISSU). This document specifies a set of common
methodologies and procedures designed to characterize the overall
behavior of a Device Under Test (DUT), subject to an ISSU event.
Status of This Memo
This document is not an Internet Standards Track specification; it is
published for informational purposes.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Not all documents
approved by the IESG are a candidate for any level of Internet
Standard; see Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc7654.
Banks, et al. Informational [Page 1]RFC 7654 Benchmarking Software Upgrade October 2015
Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction ....................................................3
2. Conventions Used in This Document ...............................4
3. Generic ISSU Process, Phased Approach ...........................4
3.1. Software Download ..........................................5
3.2. Software Staging ...........................................6
3.3. Upgrade Run ................................................6
3.4. Upgrade Acceptance .........................................7
4. Test Methodology ................................................7
4.1. Test Topology ..............................................7
4.2. Load Model .................................................8
5. ISSU Test Methodology ...........................................9
5.1. Pre-ISSU Recommended Verifications .........................9
5.2. Software Staging ...........................................9
5.3. Upgrade Run ...............................................10
5.4. Post-ISSU Verification ....................................11
5.5. ISSU under Negative Stimuli ...............................12
6. ISSU Abort and Rollback ........................................12
7. Final Report: Data Presentation and Analysis ...................13
7.1. Data Collection Considerations ............................14
8. Security Considerations ........................................15
9. References .....................................................15
9.1. Normative References ......................................15
9.2. Informative References ....................................16
Acknowledgments ...................................................16
Authors' Addresses ................................................16
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1. Introduction
As required by most Service Provider (SP) network operators, ISSU
functionality has been implemented by modern forwarding devices to
upgrade or downgrade from one software version to another with a goal
of eliminating the downtime of the router and/or the outage of
service. However, it is noted that while most operators desire
complete elimination of downtime, minimization of downtime and
service degradation is often the expectation.
The ISSU operation may apply in terms of an atomic version change of
the entire system software or it may be applied in a more modular
sense, such as for a patch or maintenance upgrade. The procedure
described herein may be used to verify either approach, as may be
supported by the vendor hardware and software.
In support of this document, the desired behavior for an ISSU
operation can be summarized as follows:
- The software is successfully migrated from one version to a
successive version or vice versa.
- There are no control-plane interruptions throughout the process.
That is, the upgrade/downgrade could be accomplished while the
device remains "in service". It is noted, however, that most
service providers will still undertake such actions in a
maintenance window (even in redundant environments) to minimize
any risk.
- Interruptions to the forwarding plane are minimal to none.
- The total time to accomplish the upgrade is minimized, again to
reduce potential network outage exposure (e.g., an external
failure event might impact the network as it operates with reduced
redundancy).
This document provides a set of procedures to characterize a given
forwarding device's ISSU behavior quantitatively, from the
perspective of meeting the above expectations.
Different hardware configurations may be expected to be benchmarked,
but a typical configuration for a forwarding device that supports
ISSU consists of at least one pair of Routing Processors (RPs) that
operate in a redundant fashion, and single or multiple forwarding
engines (line cards) that may or may not be redundant, as well as
fabric cards or other components as applicable. This does not
preclude the possibility that a device in question can perform ISSU
functions through the operation of independent process components,
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which may be upgraded without impact to the overall operation of the
device. As an example, perhaps the software module involved in SNMP
functions can be upgraded without impacting other operations.
The concept of a multi-chassis deployment may also be characterized
by the current set of proposed methodologies, but the implementation-
specific details (i.e., process placement and others) are beyond the
scope of the current document.
Since most modern forwarding devices, where ISSU would be applicable,
do consist of redundant RPs and hardware-separated control-plane and
data-plane functionality, this document will focus on methodologies
that would be directly applicable to those platforms. It is
anticipated that the concepts and approaches described herein may be
readily extended to accommodate other device architectures as well.
2. Conventions Used in This Document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
In this document, these words will appear with that interpretation
only when in ALL CAPS. Lowercase uses of these words are not to be
interpreted as carrying the significance of RFC 2119.
3. Generic ISSU Process, Phased Approach
ISSU may be viewed as the behavior of a device when exposed to a
planned change in its software functionality. This may mean changes
to the core operating system, separate processes or daemons, or even
firmware logic in programmable hardware devices (e.g., Complex
Programmable Logic Device (CPLD) or Field-Programmable Gate Array
(FPGA)). The goal of an ISSU implementation is to permit such
actions with minimal or no disruption to the primary operation of the
device in question.
ISSU may be user initiated through direct interaction with the device
or activated through some automated process on a management system or
even on the device itself. For the purposes of this document, we
will focus on the model where the ISSU action is initiated by direct
user intervention.
The ISSU process can be viewed as a series of different phases or
activities, as defined below. For each of these phases, the test
operator must record the outcome as well as any relevant observations
(defined further in the present document). Note that, a given vendor
implementation may or may not permit the abortion of the in-progress
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ISSU at particular stages. There may also be certain restrictions as
to ISSU availability given certain functional configurations (for
example, ISSU in the presence of Bidirectional Failure Detection
(BFD) [RFC5880] may not be supported). It is incumbent upon the test
operator to ensure that the DUT is appropriately configured to
provide the appropriate test environment. As with any properly
orchestrated test effort, the test plan document should reflect these
and other relevant details and should be written with close attention
to the expected production operating environment. The combined
analysis of the results of each phase will characterize the overall
ISSU process with the main goal of being able to identify and
quantify any disruption in service (from the data- and control-plane
perspective) allowing operators to plan their maintenance activities
with greater precision.
3.1. Software Download
In this first phase, the requested software package may be downloaded
to the router and is typically stored onto a device. The downloading
of software may be performed automatically by the device as part of
the upgrade process, or it may be initiated separately. Such
separation allows an administrator to download the new code inside or
outside of a maintenance window; it is anticipated that downloading
new code and saving it to disk on the router will not impact
operations. In the case where the software can be downloaded outside
of the actual upgrade process, the administrator should do so;
downloading software can skew timing results based on factors that
are often not comparative in nature. Internal compatibility
verification may be performed by the software running on the DUT, to
verify the checksum of the files downloaded as well as any other
pertinent checks. Depending upon vendor implementation, these
mechanisms may include 1) verifying that the downloaded module(s)
meet a set of identified prerequisites such as (but not limited to)
hardware or firmware compatibility or minimum software requirements
or even 2) ensuring that device is "authorized" to run the target
software.
Where such mechanisms are made available by the product, they should
be verified, by the tester, with the goal of avoiding operational
issues in production. Verification should include both positive
verification (ensuring that an ISSU action should be permitted) as
well as negative tests (creation of scenarios where the verification
mechanisms would report exceptions).
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3.2. Software Staging
In this second phase, the requested software package is loaded in the
pertinent components of a given forwarding device (typically the RP
in standby state). Internal compatibility verification may be
performed by the software running on the DUT, as part of the upgrade
process itself, to verify the checksum of the files downloaded as
well as any other pertinent checks. Depending upon vendor
implementation, these mechanisms may include verification that the
downloaded module(s) meet a set of identified prerequisites such as
hardware or firmware compatibility or minimum software requirements.
Where such mechanisms are made available by the product, they should
be verified, by the tester (again with the goal of avoiding
operational issues in production). In this case, the execution of
these checks is within the scope of the upgrade time and should be
included in the testing results. Once the new software is downloaded
to the pertinent components of the DUT, the upgrade begins, and the
DUT begins to prepare itself for upgrade. Depending on the vendor
implementation, it is expected that redundant hardware pieces within
the DUT are upgraded, including the backup or secondary RP.
3.3. Upgrade Run
In this phase, a switchover of RPs may take place, where one RP is
now upgraded with the new version of software. More importantly, the
"Upgrade Run" phase is where the internal changes made to information
and state (stored on the router, on disk, and in memory) are either
migrated to the "new" version of code, or transformed/rebuilt to meet
the standards of the new version of code, and pushed onto the
appropriate pieces of hardware. It is within this phase that any
outage(s) on the control or forwarding plane may be expected to be
observed. This is the critical phase of the ISSU, where the control
plane should not be impacted and any interruptions to the forwarding
plane should be minimal to none.
If any control- or data-plane interruptions are observed within this
stage, they should be recorded as part of the results document.
For some implementations, the two stages, as described in Section 3.2
and above, may be concatenated into one monolithic operation. In
that case, the calculation of the respective ISSU time intervals may
need to be adapted accordingly.
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3.4. Upgrade Acceptance
In this phase, the new version of software must be running in all the
physical nodes of the logical forwarding device (RPs and line cards
as applicable). At this point, configuration control is returned to
the operator, and normal device operation, i.e., outside of ISSU-
oriented operation, is resumed.
4. Test Methodology
As stated by [RFC6815], the Test Topology Setup must be part of an
Isolated Test Environment (ITE).
The reporting of results must take into account the repeatability
considerations from Section 4 of [RFC2544]. It is RECOMMENDED to
perform multiple trials and report average results. The results are
reported in a simple statement including the measured frame loss and
ISSU impact times.
4.1. Test Topology
The hardware configuration of the DUT (Device Under Test) should be
identical to the one expected to be or currently deployed in
production in order for the benchmark to have relevance. This would
include the number of RPs, hardware version, memory, and initial
software release, any common chassis components, such as fabric
hardware in the case of a fabric-switching platform, and the specific
line cards (version, memory, interfaces type, rate, etc.).
For the control and data plane, differing configuration approaches
may be utilized. The recommended approach relies on "mimicking" the
existing production data- and control-plane information, in order to
emulate all the necessary Layer 1 through Layer 3 communications and,
if appropriate, the upper-layer characteristics of the network, as
well as end-to-end traffic/communication pairs. In other words,
design a representative load model of the production environment and
deploy a collapsed topology utilizing test tools and/or external
devices, where the DUT will be tested. Note that, the negative
impact of ISSU operations is likely to impact scaled, dynamic
topologies to a greater extent than simpler, static environments. As
such, this methodology (based upon production configuration) is
advised for most test scenarios.
The second, more simplistic approach is to deploy an ITE in which
endpoints are "directly" connected to the DUT. In this manner,
control-plane information is kept to a minimum (only connected
interfaces), and only a basic data-plane of sources and destinations
is applied. If this methodology is selected, care must be taken to
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understand that the systemic behavior of the ITE may not be identical
to that experienced by a device in a production network role. That
is, control-plane validation may be minimal to none with this
methodology. Consequently, if this approach is chosen, comparison
with at least one production configuration is recommended in order to
understand the direct relevance and limitations of the test exercise.
4.2. Load Model
In consideration of the defined test topology, a load model must be
developed to exercise the DUT while the ISSU event is introduced.
This applied load should be defined in such a manner as to provide a
granular, repeatable verification of the ISSU impact on transit
traffic. Sufficient traffic load (rate) should be applied to permit
timing extrapolations at a minimum granularity of 100 milliseconds,
e.g., 100 Mbps for a 10 Gbps interface. The use of steady traffic
streams rather than bursty loads is preferred to simplify analysis.
The traffic should be patterned to provide a broad range of source
and destination pairs, which resolve to a variety of FIB (Forwarding
Information Base) prefix lengths. If the production network
environment includes multicast traffic or VPNs (L2, L3, or IPsec), it
is critical to include these in the model.
For mixed protocol environments (e.g., IPv4 and IPv6), frames should
be distributed between the different protocols. The distribution
should approximate the network conditions of deployment. In all
cases, the details of the mixed protocol distribution must be
included in the reporting.
The feature, protocol timing, and other relevant configurations
should be matched to the expected production environment. Deviations
from the production templates may be deemed necessary by the test
operator (for example, certain features may not support ISSU or the
test bed may not be able to accommodate such). However, the impact
of any such divergence should be clearly understood, and the
differences must be recorded in the results documentation. It is
recommended that a Network Management System (NMS) be deployed,
preferably similar to that utilized in production. This will allow
for monitoring of the DUT while it is being tested, both in terms of
supporting the impact analysis on system resources as well as
detecting interference with non-transit (management) traffic as a
result of the ISSU operation. It is suggested that the actual test
exercise be managed utilizing direct console access to the DUT, if at
all possible, to avoid the possibility that a network interruption
impairs execution of the test exercise.
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All in all, the load model should attempt to simulate the production
network environment to the greatest extent possible in order to
maximize the applicability of the results generated.
5. ISSU Test Methodology
As previously described, for the purposes of this test document, the
ISSU process is divided into three main phases. The following
methodology assumes that a suitable test topology has been
constructed per Section 4. A description of the methodology to be
applied for each of the above phases follows.
5.1. Pre-ISSU Recommended Verifications
The steps of this phase are as follows.
1. Verify that enough hardware and software resources are available
to complete the Load operation (e.g., enough disk space).
2. Verify that the redundancy states between RPs and other nodes are
as expected (e.g., redundancy on, RPs synchronized).
3. Verify that the device, if running protocols capable of NSR (Non-
Stop Routing), is in a "ready" state; that is, that the sync
between RPs is complete and the system is ready for failover, if
necessary.
4. Gather a configuration snapshot of the device and all of its
applicable components.
5. Verify that the node is operating in a "steady" state (that is,
no critical or maintenance function is being currently
performed).
6. Note any other operational characteristics that the tester may
deem applicable to the specific implementation deployed.
5.2. Software Staging
The steps of this phase are as follows.
1. Establish all relevant protocol adjacencies and stabilize routing
within the test topology. In particular, ensure that the scaled
levels of the dynamic protocols are dimensioned as specified by
the test topology plan.
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2. Clear, relevant logs and interface counters to simplify analysis.
If possible, set logging timestamps to a highly granular mode.
If the topology includes management systems, ensure that the
appropriate polling levels have been applied, sessions have been
established, and the responses are per expectation.
3. Apply the traffic loads as specified in the load model previously
developed for this exercise.
4. Document an operational baseline for the test bed with relevant
data supporting the above steps (include all relevant load
characteristics of interest in the topology, e.g., routing load,
traffic volumes, memory and CPU utilization).
5. Note the start time (T0) and begin the code change process
utilizing the appropriate mechanisms as expected to be used in
production (e.g., active download with TFTP, FTP, SCP, etc., or
direct install from local or external storage facility). In
order to ensure that ISSU process timings are not skewed by the
lack of a network-wide synchronization source, the use of a
network NTP source is encouraged.
6. Take note of any logging information and command-line interface
(CLI) prompts as needed. (This detail will be vendor specific.)
Respond to any DUT prompts in a timely manner.
7. Monitor the DUT for the reload of the secondary RP to the new
software level. Once the secondary has stabilized on the new
code, note the completion time. The duration of these steps will
be recorded as "T1".
8. Review system logs for any anomalies, check that relevant dynamic
protocols have remained stable, and note traffic loss if any.
Verify that deployed management systems have not identified any
unexpected behavior.
5.3. Upgrade Run
The following assumes that the software load step and upgrade step
are discretely controllable. If not, maintain the aforementioned
timer and monitor for completion of the ISSU as described below.
1. Note the start time and initiate the actual upgrade procedure.
2. Monitor the operation of the secondary route processor while it
initializes with the new software and assumes mastership of the
DUT. At this point, pay particular attention to any indications
of control-plane disruption, traffic impact, or other anomalous
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behavior. Once the DUT has converged upon the new code and
returned to normal operation, note the completion time and log
the duration of this step as "T2".
3. Review the syslog data in the DUT and neighboring devices for any
behavior that would be disruptive in a production environment
(line card reloads, control-plane flaps, etc.). Examine the
traffic generators for any indication of traffic loss over this
interval. If the Test Set reported any traffic loss, note the
number of frames lost as "TPL_frames", where TPL stands for
"Total Packet Loss". If the Test Set also provides outage
duration, note this as "TPL_time". (Alternatively, TPL_time may
be calculated as (TPL / Offered Load) * 1000. The units for
Offered Load are packets per second; the units for TPL_time are
milliseconds.)
4. Verify the DUT status observations as per any NMS managing the
DUT and its neighboring devices. Document the observed CPU and
memory statistics both during and after the ISSU upgrade event,
and ensure that memory and CPU have returned to an expected
(previously baselined) level.
5.4. Post-ISSU Verification
The following describes a set of post-ISSU verification tasks that
are not directly part of the ISSU process, but are recommended for
execution in order to validate a successful upgrade.
1. Configuration delta analysis
Examine the post-ISSU configurations to determine if any changes
have occurred either through process error or due to differences
in the implementation of the upgraded code.
2. Exhaustive control-plane analysis
Review the details of the Routing Information Base (RIB) and FIB
to assess whether any unexpected changes have been introduced in
the forwarding paths.
3. Verify that both RPs are up and that the redundancy mechanism for
the control plane is enabled and fully synchronized.
4. Verify that no control-plane (protocol) events or flaps were
detected.
5. Verify that no L1 and or L2 interface flaps were observed.
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6. Document the hitless operation or presence of an outage based
upon the counter values provided by the Test Set.
5.5. ISSU under Negative Stimuli
As an OPTIONAL Test Case, the operator may want to perform an ISSU
test while the DUT is under stress by introducing route churn to any
or all of the involved phases of the ISSU process.
One approach relies on the operator to gather statistical information
from the production environment and determine a specific number of
routes to flap every 'fixed' or 'variable' interval. Alternatively,
the operator may wish to simply preselect a fixed number of prefixes
to flap. As an example, an operator may decide to flap 1% of all the
BGP routes every minute and restore them 1 minute afterwards. The
tester may wish to apply this negative stimulus throughout the entire
ISSU process or, most importantly, during the run phase. It is
important to ensure that these routes, which are introduced solely
for stress proposes, must not overlap the ones (per the load model)
specifically leveraged to calculate the TPL_time (recorded outage).
Furthermore, there should not be 'operator-induced' control-plane
protocol adjacency flaps for the duration of the test process as it
may adversely affect the characterization of the entire test
exercise. For example, triggering IGP adjacency events may force
recomputation of underlying routing tables with attendant impact to
the perceived ISSU timings. While not recommended, if such trigger
events are desired by the test operator, care should be taken to
avoid the introduction of unexpected anomalies within the test
harness.
6. ISSU Abort and Rollback
Where a vendor provides such support, the ISSU process could be
aborted for any reason by the operator. However, the end results and
behavior may depend on the specific phase where the process was
aborted. While this is implementation dependent, as a general
recommendation, if the process is aborted during the "Software
Download" or "Software Staging" phases, no impact to service or
device functionality should be observed. In contrast, if the process
is aborted during the "Upgrade Run" or "Upgrade Accept" phases, the
system may reload and revert back to the previous software release,
and, as such, this operation may be service affecting. Where vendor
support is available, the abort/rollback functionality should be
verified, and the impact, if any, quantified generally following the
procedures provided above.
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7. Final Report: Data Presentation and Analysis
All ISSU impact results are summarized in a simple statement
describing the "ISSU Disruption Impact" including the measured frame
loss and impact time, where impact time is defined as the time frame
determined per the TPL_time reported outage. These are considered to
be the primary data points of interest.
However, the entire ISSU operational impact should also be considered
in support of planning for maintenance, and, as such, additional
reporting points are included.
Software download / secondary update T1
Upgrade/Run T2
ISSU Traffic Disruption (Frame Loss) TPL_frames
ISSU Traffic Impact Time (milliseconds) TPL_time
ISSU Housekeeping Interval T3
(Time for both RPs up on new code and fully synced - Redundancy
restored)
Total ISSU Maintenance Window T4 (sum of T1+T2+T3)
The results reporting must provide the following information:
- DUT hardware and software detail
- Test Topology definition and diagram (especially as related to the
ISSU operation)
- Load Model description including protocol mixes and any divergence
from the production environment
- Time Results as per above
- Anomalies Observed during ISSU
- Anomalies Observed in post-ISSU analysis
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It is RECOMMENDED that the following parameters be reported as
outlined below:
Parameter Units or Examples
---------------------------------------------------------------
Traffic Load Frames per second and bits per second
Disruption (average) Frames
Impact Time (average) Milliseconds
Number of trials Integer count
Protocols IPv4, IPv6, MPLS, etc.
Frame Size Octets
Port Media Ethernet, Gigabit Ethernet (GbE),
Packet over SONET (POS), etc.
Port Speed 10 Gbps, 1 Gbps, 100 Mbps, etc.
Interface Encaps Ethernet, Ethernet VLAN, PPP,
High-Level Data Link Control (HDLC), etc.
Number of Prefixes Integer count
flapped (ON Interval) (Optional) # of prefixes / Time (min.)
flapped (OFF Interval) (Optional) # of prefixes / Time (min.)
Document any configuration deltas that are observed after the ISSU
upgrade has taken effect. Note differences that are driven by
changes in the patch or release level, as well as items that are
aberrant changes due to software faults. In either of these cases,
any unexpected behavioral changes should be analyzed and a
determination made as to the impact of the change (be it functional
variances or operational impacts to existing scripts or management
mechanisms).
7.1. Data Collection Considerations
When a DUT is undergoing an ISSU operation, it's worth noting that
the DUT's data collection and reporting of data, such as counters,
interface statistics, log messages, etc., may not be accurate. As
such, one should not rely on the DUT's data collection methods, but
rather, should use the test tools and equipment to collect data used
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for reporting in Section 7. Care and consideration should be paid in
testing or adding new test cases, such that the desired data can be
collected from the test tools themselves, or other external
equipment, outside of the DUT itself.
8. Security Considerations
All BMWG memos are limited to testing in a laboratory Isolated Test
Environment (ITE), thus avoiding accidental interruption to
production networks due to test activities.
All benchmarking activities are limited to technology
characterization using controlled stimuli in a laboratory environment
with dedicated address space and the other constraints [RFC2544].
The benchmarking network topology will be an independent test setup
and MUST NOT be connected to devices that may forward the test
traffic into a production network or misroute traffic to the test
management network.
Further, benchmarking is performed on a "black-box" basis, relying
solely on measurements observable external to the Device Under Test /
System Under Test (DUT/SUT).
Special capabilities should not exist in the DUT/SUT specifically for
benchmarking purposes. Any implications for network security arising
from the DUT/SUT should be identical in the lab and in production
networks.
9. References
9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC2544] Bradner, S. and J. McQuaid, "Benchmarking Methodology for
Network Interconnect Devices", RFC 2544,
DOI 10.17487/RFC2544, March 1999,
<http://www.rfc-editor.org/info/rfc2544>.
Banks, et al. Informational [Page 15]RFC 7654 Benchmarking Software Upgrade October 2015
9.2. Informative References
[RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection
(BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010,
<http://www.rfc-editor.org/info/rfc5880>.
[RFC6815] Bradner, S., Dubray, K., McQuaid, J., and A. Morton,
"Applicability Statement for RFC 2544: Use on Production
Networks Considered Harmful", RFC 6815,
DOI 10.17487/RFC6815, November 2012,
<http://www.rfc-editor.org/info/rfc6815>.
Acknowledgments
The authors wish to thank Vibin Thomas for his valued review and
feedback.
Authors' Addresses
Sarah Banks
VSS Monitoring
Email: sbanks@encrypted.net
Fernando Calabria
Cisco Systems
Email: fcalabri@cisco.com
Gery Czirjak
Juniper Networks
Email: gczirjak@juniper.net
Ramdas Machat
Juniper Networks
Email: rmachat@juniper.net
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