1. Bandwidth Test Controller (BWCTL) Speaker: Shin-Fu Huang Date: 2009/10/08 1

2. Outline Architecture of BWCTL Building BWCTL Applications of BWCTL – BWCTLD(bwctld.conf, bwctld.limits, bwctld.keys) – BWCTL Reference 2

3. Architecture of BWCTL Source : http://www.internet2.edu/pubs/bwctl-cookbook.pdf 3

4. Architecture of BWCTL(Cont.) Source : http://www.internet2.edu/pubs/bwctl-cookbook.pdf 4

5. Building the Application tar –zxvf bwctl-1.3.tar.gz cd bwctl-1.3./configure --prefix=/ami – --prefix is only needed if you don't like the default – (/usr/local on most systems) make make install 5

6. Applications of BWCTL bwctl (Client) bwctld (Deamon) 6

7. BWCTLD bwctld.conf – Configuration file for the bwcltd daemon bwctld.limits – Authentication(who) – Authorization(what) bwctld.keys – Be used to hold the identity/AES keys pairs needed for bwctld to authenticate users 7

8. bwctld.conf var_dir – Directory where bwctld.pid file is stored user – Specifies the uid the bwctld process will run as group – Specifies the gid the bwctld process will run as 8

9. bwctld.limits allow_open_mode (on) – This limit is only useful if the class is assigned to a netmask. It is used to limit specific IP/netmask identities to only encrypted or authenticated mode transactions or to allow open mode. allow_tcp (on) – Allow TCP Iperf tests for userclass. allow_udp (off) – Allow UDP Iperf tests for userclass. – Security issue(UDP no congestion control) 9

10. bwctld.limits(Cont.) bandwidth – Maximum amount of bandwidth to allow userclass to use in a UDP Iperf test. 0 indicates unlimited by policy, but remember this is checked all the way to the root of the hierarchy. – If you want an unlimited userclass, your root must be unlimited, and the whole path down to the given userclass. 10

11. bwctld.limits(Cont.) Hierarchical Limitclasses root allow_udp=on ncnu allow_udp=off jailregularlocal 11

12. bwctld.limits(Cont.) root: – limit root with \ bandwidth=900m, \ allow_udp=on, \ allow_tcp=on, \ allow_open_mode=off 12

13. bwctld.limits(Cont.) default: – limit regular with parent=root, \ duration=30, \ allow_tcp=on, \ allow_udp=off, \ allow_open_mode=on 13

14. bwctld.limits(Cont.) ncnu: – limit ncnu with parent=root, \ allow_open_mode=on, \ allow_udp=off, \ allow_tcp=on 14

15. bwctld.limits(Cont.) Assign – assign default regular – net subnet assign net 10.10.0.0/16 ncnu assign net 2001:e10:6840::/48 ncnu assign net 2001:288:c001::/48 ncnu – user user Assign a specific user to a given userclass. The user must be defined in the bwctld.keys file. assign user xinfu root 15

16. bwctld.keys Username and AES Key Rules: – Usernames are limited to 16 characters – AES key is a 128 bit session key – AES key is not encrypted in the keys file, use UNIX permissions to protect it – Can use a pass phrase to generate the AES key – Use aespasswd to add pass phrase generated keys into the keys file – Client: application prompts user for pass phrase 16

17. bwctld.keys(Cont.) aespasswd – To create a new key file use the ‘-n’ option aespasswd -n -f bwctld.keys xinfu – Add User aespasswd -f bwctld.keys ccc – Delete User aespasswd -d -f bwctld.keys ccc 17

18. BWCTL(Cont.) SYNOPSIS – bwctl [options] -c recvhost -s sendhost From sendhost to recvhost – bwctl [options] -c recvhost Send to recvhost – bwctl [options] -s sendhost Receive from sendhost 18

19. BWCTL(Cont.) Testing Authentication Options – Within a single authentication domain bwctl -A AE AESKEY myname -s hostA -c hostB – Between different authentication domains bwctl -s hostA AE AESKEY myname -c hostB AE AESKEY othername 19

20. BWCTL(Cont.) OPTIONS -u – UDP test. -T tool (iperf) – Specify which throughput tester to use: iperf, thrulay, nuttcp -b bandwidth (1Mb) – Limit UDP send rate to bandwidth (bits/sec). 20

21. BWCTL(Cont.) -l len – length of read/write buffers (bytes). -P nStreams (1) – Number of concurrent streams for the test. -t time (10) – Duration of test (seconds). 21

22. BWCTL(Cont.) Output Arguments -f units – Specify the units for the tool to use when displaying the results. – Iperf: k (Kilobits per second) K (Kilobytes per second) m (Megabits per second) M (Megabytes per second) 22

23. Reference Bandwidth Test Controller (BWCTL) – http://www.internet2.edu/performance/bwctl/ 23