MGRID: Network Testing and
Performance
Charles J. Antonelli
Center for Information Technology Integration
University of Michigan
MGRID NTAP Project
• NTAP : Network Testing and Performance
• Purpose : provide a secure and extensible
network testing and performance tool
invocation service at U-M
• Service based on Globus
• Runs on dedicated nodes attached to routers
in a VLAN environment
MGRID Architecture
MGRID Portal
User Workstation
Apache
mod ssl
mod kct
mod kx509
mod mod
php
jk
SSL – Client Certificate required
3
4
Kerberos
5
KCA
KDC
Tomcat
6
GSI
CHEF
6
LDAP
Authorization
Kerberos V5
KCT
SASL
8
libpkcs11
Resource Mng
Resource
kx509
2
Kerberos
kinit
1
Grid Resource
GateKeeper
Browser
SASL
7
LDAP
Authorization
MGRID NTAP Project
• Initial work implemented a bandwidth
reservation tool:
– Securely modifies network switch configurations
to provide differentiated services
– Based on GARA
• “General-purpose Architecture for Reservation
and Allocation”
• Layered on Globus
• Implements role-based authorization
• Includes scheduler for future reservations
MGRID NTAP Project
• Added modular, fine-grained authorization
– Added signed group membership(s) to reservation data
– Now provides two authorization methods:
• Keynote policy engine / AFS PTS group service
• PERMIS policy engine / LDAP group service
• Generalized from bandwidth reservations to the
ability to run securely arbitrary programs at a Grid
service endpoint
– Designed to easily add functionality
– Network testing tools being used now
• Iperf, traceroute, ping, owamp, etc
MGRID NTAP Architecture
Host A
Host B
Router 1
Router 2
Router 3
Web Portal
GSI
GSI
GSI
PMP 1
Attribute Callout
Flat File
AFS PTS
PERMIS
PMP 2
PMP 3
MGRID NTAP Project
• Multihomed PMP support
– One routing table per VLAN
– Routing policy selects routing table based on
source address of outgoing packet
– Emulates a default route per virtual interface
• Path discovery
– Use traceroute to obtain routing information
– Use network topology databases to map network
segments to PMP pairs
MGRID NTAP Project
• PERMIS authorization
– User, Target, Action
– Attribute, policy certificates
– Policy engine
• Production hardening
–
–
–
–
Error handling/recovery
Cleanup/restart
Log file management
Deployment packaging
MGRID NTAP Project
• Performance measurement
– Deployment to ITCom lab
• Output Database
– Permanent, secure storage of results
– Searches and aggregations
– Throughput/latency matrix
• Host Endpoint Testing
– The “last mile” segment
– Secure download of signed binaries
MGRID NTAP Project
Demonstration
Host A
192.168.10.19
192.168.10.1
Host B
192.168.20.99
R1
192.168.10.50
PMP 1
10.1.1.1/30
10.1.1.2/30
R2
192.168.20.50
PMP 2
MGRID NTAP Project
Performance test, step 1
– locate the first PMP, the performance
machine “nearest” to the tester
MGRID NTAP Project
Performance test, step 2
– discover network path (i.e. routers)
MGRID NTAP Project
Performance test, steps 3, 4, …, n
– run pairwise tests between “adjacent” PMPs
• ideally, this will capture hop-by-hop network data
• sometimes there are network “holes”
– lastly, timestamp and store the output for postprocessing (generate graphs, check for empirical
anomalies, etc)
Any Questions?
http://mgrid.umich.edu