Bradley R. Smith, PhD
Computer Engineering Department
Jack Baskin School of Engineering
University of California, Santa Cruz
Santa Cruz, CA 95064
Voice: (831)459-2370
Fax: (831)459-4829

2/28/2018: here is the ITS recruitment video.

4/5/2016: here is a video of my talk at the 2016 CENIC Annual Conference on the virtual network labs I've developed for CE 151.

5/5/2015: "It is important to note that there will be no administrative growth from State funds, and we will continue to build upon our efficiency and costs saving efforts that have already produced over $660 million in savings and alternative revenues." -- Janet Napolitano, UC President

4/26/2015: The Santa Cruz Warriors... D-League Champions!

1/4/2014: Another interesting graphic showing how people respond to Pew surveyors general first question of how their day is going, organized by country. General trend is the richer the country the more negative the response... except the US. Not sure what this means... but is interesting). (From a Washington Post article, covers ~48,000 responses from the past year.)

12/18/11: Interesting graphic on the relative allocation of resources to R&D by different countries... is good to know that, even though the California is squandering its strength in creating the future, the nation is still in a leadership position (although this is only a snapshot... would be interesting to have a sense of national trends).

These articles from the Los Angeles Times (9/4/09) and the New York Times (11/19/09) that give a good perspective on the plight of higher education in California.

8/12/09: here's an article that illustrates very clearly how the wolves are circling the wounded UC system. The residents of California should be very clear how the current governor and legislature are presiding over the dismantling of the greatest public research university the world has known, and the source of innovation driving the California economy.

6/16/09: here's a very good summary of the state budget situation from the Mercury News. Here is the original article (with a link to an interactive version of the graphic).

This homepage provides information about my:

Current Research

My research interests, in general, are in distributed systems and computer communications. Currently, my specific interests are in the areas of policy-based routing, formalizing trust in the context of a routing computation, object routing, and the application of these technologies to the improvement of the security and robustness of Internet-based systems.

The current Internet can be characterized as realizing a cloud model of topology control due to its dependence on a pre-computed, distributed route computation (i.e. no single router computes a complete path through an internet), and hop-by-hop forwarding where forwarding decisions are made independently at each router in a path through the network. In contrast, recent proposals for the control of Internet topology computation realize a string model of topology control due to their dependence on on-demand, centralized route computations performed at the ingress router, and virtual-circuit style, source-specified forwarding implemented by source routing or some form of path setup.

There are a number of benefits of the cloud model compared with the string model. The cloud model is more robust in the sense that, since control of state in a cloud is distributed with the state itself (e.g. packet forwarding state is controlled by a co-located routing process), the loss of any component of the network only results in the loss of functionality at that node. I.e. the distributed nature of clouds tends to localize the affects of failures in a network. The cloud model is more responsive and efficient in that, due to the autonomous control of network state, it only requires simplex communication of events in an internet to adapt to changes. For example, in the event of a link cost change in an internet, routers only need to be notified of the event (to change their local forwarding state, if necessary), and do not need to engage in any further communication to coordinate their response to the event.

The goal of my PhD work was to enhance the Internet's current distributed, hop-by-hop routing architecture to support a default multi-policy forwarding model as compared with the traditional default single-policy forwarding model. The concrete implication of this change in assumptions is that the dramatic jump in expected policy-route request rates makes the costs of on-demand, string-style policy-based routing unacceptable. This change requires efficient mechanisms for computing and implementing policy-constrained topologies. Therefore, the focus of my dissertation was the design and analysis of new policy-based routing algorithms, and the application of these algorithms to the security and manageability of unicast and multicast services.


Bradley R. Smith "Dominant Network Slices," IEEE Military Communications Conference (MILCOM 2023), Boston, MA. 30 October - 3 November, 2023.

JJ Garcia-Luna-Aceves, Bradley R. Smith, Judith T. Samson "SCRIP: Safe and Cycle-Free Multi-Path Routing," IEEE Military Communications Conference (MILCOM 2022), Rockville, MD. 28 November - 2 December, 2022.

JJ Garcia-Luna-Aceves, Bradley R. Smith, Judith T. Samson "QoS Routing Using Dominant-Distance Vectors," IEEE/ACM International Symposium on Quality of Service (IWQoS 2022), Virtual. June 10-12, 2022.

Bradley R. Smith and Judith T. Samson "Herding Packets: Properties Needed of Metrics for Loop-Free & Best Forwarding Paths," International Conference on Computing, Networking and Communications (ICNC 2017), Silicon Valley, USA. January 26-29, 2017.

Christopher Wilks et al. "The Cancer Genomics Hub (CGHub): overcoming cancer through the power of torrential data", Database. 2014.

Bradley R. Smith and Lincoln Thurlow. "Practical Multipath Load Balancing with QoS", Proceedings (PDF) International Conference on Computing, Networking and Communications. January, 2013.

Bradley R. Smith. "Using Dijkstra to Compute Hop-by-Hop QoS Paths" Proceedings (PDF) 1st Workshop on Context-aware QoS Provisioning and Management for Emerging Networks, Applications and Services (ContextQoS), 20th International Conference on Computer Communication Networks (ICCCN '11). August, 2011.

Stephen Dabideen, Bradley R. Smith, and J.J. Garcia-Luna-Aceves. "An End-to-End Approach to Secure Routing in MANETs" Security and Communication Networks, Wiley. Vol. 3, Issue 2-3, pp. 130-149, March-June 2010.

Stephen Dabideen, Bradley R. Smith and J.J. Garcia-Luna-Aceves. "An End-to-End Solution for Secure and Survivable Routing in MANET(s)," 7th International Workshop on the Design of Reliable Commuication Networks (DRCN 2009), Washington D.C. October, 2009.

Stephen Dabideen, Bradley R. Smith and J.J. Garcia-Luna-Aceves. "The Case for End-to-End Solutions to Secure Routing in MANETs," International Workshop on Security, Privacy and Trust of Computer and Cyber-Physical Networks (SecureCPN); 18th International Conference on Computer Communication and Networks (ICCCN '09), San Francisco, CA. August, 2009.

Bradley R. Smith and J.J. Garcia-Luna-Aceves. "Best Effort Quality-of-Service," 17th International Confereonce on Computer Communications and Networks (ICCCN '08), St Thomas, U.S. Virgin Islands. August, 2008.

Bradley R. Smith and J.J. Garcia-Luna-Aceves. "Efficient Policy-Based Routing Without Virtual Circuits," First International Conference on Quality of Service in Heterogeneous Wired/Wireless Networks (QSHINE '04), Dallas, Texas. October, 2004.

Bradley R. Smith and J.J. Garcia-Luna-Aceves. "Policy-Aware Connectionless Routing," First International Workshop on QoS Routing (WQoSR '04), Barcelona, Spain. October, 2004.

Bradley R. Smith, "Efficient Policy-Based Routing in the Internet"(PDF), PhD Dissertation, Computer Science, University of California, Santa Cruz, CA 95064. September, 2003.

G. Denker, J.J. Garcia-Luna-Aceves, J. Meseguer, P.C. Olveczky, J. Raju, B. Smith, and C.L. Talcott, "Specification and Analysis of a Reliable Broadcasting Protocol in Maude", Proc. 37th Allerton Conference on Communications, Control, and Computing, Sept. 22-24, 1999.

Bradley R. Smith and J.J. Garcia-Luna-Aceves, "Efficient Security Mechanisms for the Border Gateway Routing Protocol" (PDF), Computer Communications (Elsevier), Vol. 21, No. 3, 1998, pp. 203-210.

Bradley R. Smith, "Securing Distance Vector Routing Protocols" (PDF), M.S. Thesis, Computer Science, University of California, Santa Cruz, CA 95064, June 1997.

Bradley R. Smith, Shree Murthy, and J.J. Garcia-Luna-Aceves, "Securing Distance Vector Routing Protocols" (PDF), Proc. Internet Society Symposium on Network and Distributed System Security, San Diego, California, February 1997.

Bradley R. Smith and J.J. Garcia-Luna-Aceves, "Securing the Border Gateway Routing Protocol" (PDF), Proc. Global Internet '96, London, UK, 20-21 November 1996.


US 11,621,912: Bradley R. Smith, "Network Congestion Reduction Using Boolean Constrained Multipath Routing" (April 4, 2023)

US 11,134,007: Bradley R. Smith, "Network Congestion Reduction Using Boolean Constrained Multipath Routing" (September 28, 2021)

US 9,197,544: Bradley R. Smith, "Comprehensive multipath routing for congestion and quality-of-service in communication networks" (November 24, 2015)

US 7,725,596: J.J. Garcia-Luna-Aceves and B. Smith, "System and Method for Resolving Network Layer Anycast Addresses to Network Layer Unicast Addresses" (May 25, 2010)

US 7,577,754: J.J. Garcia-Luna-Aceves and B. Smith, "System and Method for Controlling Access to Content Carried in A Caching Architecture" (August 18, 2009)

US 7,565,450: J.J. Garcia-Luna-Aceves and B. Smith, "System and Method for Using a Mapping between Client Addresses and Addresses of Caches To Support Content Delivery" (July 21, 2009)

US 7,552,233: J. Raju, J.J. Garcia-Luna-Aceves and B. Smith, "System and method for information object routing in computer networks" (June 23, 2009)

US 7,343,422: J.J. Garcia-Luna-Aceves and B. Smith, "System and Method for Using Uniform Resource Locators to Map Application Layer Content Names to Network Layer Anycast Addresses" (March, 2008)

Graduate Studies

I found this interesting article by Jason Hong in the CACM giving advice on how to succeed in PhD work. In it he referenced what he call's Heilmeier's Catechism, which is a set of questions credited to George Heilmeier that anyone proposing a research project or product development effort should be able to answer. Here are the questions:
  1. What are you trying to do? Articulate your objectives using absolutely no jargon.
  2. How is it done today, and what are the limits of current practice?
  3. What's new in your approach and why do you think it will be successful?
  4. Who cares?
  5. If you're successful, what difference will it make?
  6. What are the risks and the payoffs?
  7. How much will it cost?
  8. How long will it take?
  9. What are the midterm and final "exams" to check for success?


"The mark of the immature man is that he wants to die nobly for a cause. The mark of the mature man is that he wants to live humbly for one." - J.D. Salinger

"The secret to doing good research is always to be a little underemployed. You waste years by not being able to waste hours." - Amos Tversky

"Life is 20% what happens to you and 80% what you do about it."

Between stimulus and response there is a space.
In that space is our power to choose our response.
In our response lies our growth and our freedom.

Victor Frankl
Psychiatrist and Holocaust survivor

"Do not judge me by my successes, judge me by how many times I fell down and got back up again." - Nelson Mandela

"I have learned that success is to be measured not so much by the position that one has reached in life as by the obstacles which he has overcome while trying to succeed." - Booker T. Washington

"Calamity is the touchstone of a brave mind." - Lucius Annaeus Seneca

The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood, who strives valiantly, who errs and comes up short again and again, because there is no effort without error or shortcoming... his place shall never be with those cold and timid souls who knew neither victory nor defeat.
- Teddy Roosevelt, April 1910

''We may come to at least one conclusion: that morality can exist only among the members of a society equipped to teach and enforce it; and that an interstate morality awaits the formation of an international organization dowered with the physical power and the public opinion to maintain an international law. Till then the nations will be as beasts in the jungle; and whatever principles their governments may profess, their practice will be that of The Prince.'' - Will Durant (author of ''The Story of Civilization'') commenting on Machiavelli's ''The Prince''

''It is better that the guilty should remain unpunished than that the innocent should be condemned.'' - Trajan... Roman emperor (98-117 AD)

Brandolini's Bullshit Asymetry principle: "The amount of energy it takes to refute bullshit is an order of magnitude greater than to produce it."

A hopeful corrolary to Brandolini:)... The Pheasant and the Bull

The OODA Loop: Observe, Orient, Decide, Act - USAF Colonel John Boyd

Whether you believe you can or you can't, you're right.

I've seen things you people wouldn't believe...


Never attribute to malice that which is adequately explained by stupidity (Hanlon's Razor).

From "Battle Cry of Freedom" (by James McPherson) regarding Grant's reaction following the Confederacy's surrender: Having given birth to a reunited nation, he experienced a post-partum melancholy. "I felt . . . sad and depressed," Grant wrote, "at the downfall of a foe who had fought so long and valiantly, and had suffered so much for a cause, though that cause was, I believe, one of the worst for which a people ever fought."

"I never would have drawn my sword in the cause of America if I could have conceived that thereby I was helping to found a nation of slaves." - Marquis de Lafayette

"The gods are not to be feared; death cannot be felt; the good can be won; all that we dread can be conquered." - Epicurus

"A leader is a dealer in hope." - Napolean

"El riesgo siempre vive" from Aliens... my translation is "life is a risk," Alicia's translation (which I'd trust more:) is "there is always risk."

The Four Agreements by Don Miguel Ruiz: (1) Be impeccable with your word; (2) Don't take anything personally; (3) Don't make assumptions; (4) Always do your best.

"Rejoicing not in the many but in the probity of the few, we toil for truth alone." - William of Conches

"If I did not accomplish great things, I died in their pursuit." - Don Quixote

"Wisdom doesn't necessarily come with age. Sometimes age just shows up all by itself." - The Pickles cartoon on New Years Day 2020:).

"If we want the rewards of being loved we have to submit to the mortifying ordeal of being known." - a Facebook posting my sister (Dylan) shared.

"'s hard, it's really, really hard, in fact damned near impossible, to exercise power without it having some unexpected consequences." - from The Dresden Chronicles

"Never argue with stupid people. They will drag you down to their level and beat you with their experience." (a corollary to Brandolini's Assymetry Principle? ...see above) - often credited to Mark Twain, but evidently from Yule Brenner (and possibly derived from Proverbs (26:4)... though be sure to read 26:5:).