It was 9:20 Tuesday morning and I was sitting in the office of Agnes Brown. Hers is a corner office. The windows look out over South Dearborn Street in Chicago. The curtains on the windows are drab and worn. All of the decor is in sharp contrast to the plum location of the office. The office is spacious but very nearly barren of furniture. The most prominent piece of furniture, indeed the only piece of any note, is her desk. Rather than facing toward the door, in the natural position, the desk faces away from the door and toward the window opposite the door. I can understand why. The office is on the seventh floor and the view out the window, while not spectacular, is nicer than that of the hallway. The window faces west where the view is dominated by the Sears Tower.
Agnes was perched on the edge of the desk, with one foot on the floor. It would have been awkward for her to sit at her desk at that moment, as she would have to turn her back to all of the people in the room. Those people were Jonny, Lisa, and me. In another forty-five minutes people from the NSA would be coming to discuss the money mill.
I leaned on the window sill. Lisa and Jonny sat in straight-back chairs. Jonny had turned his around and was leaning forward with his arms crossed over the back of the chair.
I was nervous as I waited. The NSA is the country's foremost authority on cryptology. The acronym stands for National Security Agency, although some joke that it actually stands for Never Say Anything or No Such Agency. Created by Harry Truman following World War II, the mandate of the NSA is to listen to (and decode) all foreign communications of interest to the United States. The NSA is known to be the world's largest employer of mathematicians and the largest buyer of computer hardware. No other organization in the world has more expertise in cryptology. No other organization in the world has better code breakers.
Adding to my unease was the fact that Jonny and Agnes weren't any less nervous than I was. Throughout our conversation Jonny was tapping on his shoe with his pen as usual, but the tempo was faster and he skipped a beat occasionally as he shot a nervous glance in Agnes' direction.
For her part, Agnes Brown seemed to be more irritable than nervous. She met each of Jonny's glances with a level stare, followed by a quick glance at his tapping pen. For the past several minutes Jonny had been ranting about the controversies that always seem to go hand-in-hand with cryptology.
He paused now as he walked over to a small coffee machine which sat on a small table near the window. There was no sink in the room and the machine did not have a water feed of its own. Instead, there were several plastic milk jugs of water. Jonny filled the machine using the remaining water in one of these jugs and placed the empty jug under the table, along with two other jugs. Next he disposed of the old filter and coffee grounds in a waste basket under the table. They were using a plastic grocery bag as a liner for the waste basket. Beside the machine was an assortment of coffee blends: mountain, regular, de-caff, French roast, and almond vanilla. Jonny chose the regular.
Jonny didn't say anything while making the coffee, but having finished, he now resumed his story where he had left off.
``Everybody always blames new technology for life's problems,'' he said. ``Yeah, it's true that the booming progress of computers --- the Internet and telecommunications --- has opened up a whole new area of crime, and I'll be the first to admit that the Bureau has been slow to keep up. We are only beginning to come to grips with computer crime. You're seeing the leading edge of our hacker-cracker methods in this investigation... I shouldn't be telling you that, seeing as how you're still a suspect, at least officially.''
I wasn't surprised that the FBI was lagging in this area. ``I suppose there is always a transient period when new technology is first introduced where the crooks have the upper-hand until the law enforcement people come up to speed with the new environment,'' I offered.
``Hey, you make it sound like the Bureau is a bunch of bumbling bozos man,'' Jonny objected. ``I didn't mean to make it sound that bad. And we haven't fumbled computer crime yet --- at least not big-time. Of course if we blow this case, and it is leaked to the public, it would be a major embarrassment.''
Agnes turned to me and added quickly and pointedly, ``You'd be the first person we'd investigate for any leaks, Carl.''
Jonny apparently hadn't finished making his point about blaming technology for he then went on to say, ``When cars were invented they were a big improvement over horses and walking, but they also made it easier to make a clean get-away from the scene of a crime. Does this mean that cars should be banned? Or that they should be blamed for all of society's problems?'' (I resisted the temptation to reply in the affirmative just to goad him into a big debate over pollution, safety, and the like.) ``No,'' Jonny answered in reply to his own rhetorical question. ``Really, the situation was unchanged because the cops also had new cars. Technology gives better tools to the crooks but also to the cops.
``Man, think of all the other examples,'' Jonny continued. ``Paper money is easier to carry than heavy coins, but it is also easier to counterfeit. Airplanes are better than cars for long distances but airplanes put a large concentration of people into a confined space making them vulnerable to hijacking and terrorism.
``Part of the price we pay for progress is that crooks can make use of the new technology as easily as the rest of us can. Technology doesn't discriminate.
``That goes both ways. Any technology that crooks use, can also be used against them. The way I see it, the playing field is level and always will be. Technology doesn't change that.''
The coffee was done by now and Jonny served everybody, starting with Agnes and ending with me. The small coffee-maker brewed just enough coffee to fill our four cups with a small amount left over. I don't particularly like coffee, but when I do have it I like it black without sugar. Adding cream and sugar only makes a distasteful drink worse in my opinion.
``This millwright dude might be able to exploit weaknesses in the bank network to steal money, and he might be a hot-shot crypto guy, but we can match him with the same technology. Hell, we can call in the NSA.''
``That shouldn't be necessary Jonny,'' Agnes interjected firmly. ``The NSA is coming only to comment on the strength of DES.''
I'd heard about the rivalry between government agencies and I suspect this was an example of where the rivalry was blocking the most efficient path to a solution. It was clear to me that the FBI didn't really have the resources to deal with hackers as skilled in cryptology as the millrace team appeared to be.
Lisa chimed in with an anecdote about the invention of cars helping crooks. According to Lisa, Clyde --- of Bonnie and Clyde fame --- wrote a letter to Henry Ford congratulating him on the speed of his new cars. Clyde stated that Ford automobiles made excellent get-away vehicles and thanked Henry. Lisa insisted that this was a true story.
I took a sip of my coffee. Jonny had already finished his. He walked over to the table and poured himself another cup. Then he carried the pot over and topped off Lisa's cup.
Showing a weakness in character, I opened up a can of worms. ``Hey Jonny, if a level playing field is all the FBI asks, then why impose restrictions on key sizes? Why ask for legislation?''
Agnes cut in. ``We didn't invite you here to discuss politics Mr. Raymond,'' she snapped.
``I'll give them until 10:30,'' Agnes continued as she pushed her chair back from the desk and stood up. She walked across the room to the coffee pot, found it empty, glanced at Jonny, and began to prepare a fresh pot of coffee.
``They called this meeting, the least they can do is be on time,'' she muttered. From what I had heard it had been Agnes' superior, not the NSA, that had called the meeting. I said nothing.
Agnes filled the machine with water from one of the gallon jugs under the table. She continued to mutter under her breath as she tried to peel a filter away from the others, but instead peeled off two or three. It took a while for her to separate a single filter, and she muttered under her breath all the while. Picking up a pair of scissors from the counter beside the machine, she cut open an envelope of coffee grinds, dumped them in the machine, and jabbed the `brew' button with her finger. I noticed she made de-caff this time. She stood and glared at the machine while the coffee brewed, as if she expected the machine to quit the moment she turned her back. Finally, apparently satisfied that she had intimidated the machine into loyal service, she whirled around and headed back to her desk.
``What time do you have, Jonny,'' she snapped.
``10:11,'' came the reply.
``When these people do finally show up, let me do the talking, understand?'' Agnes said to me.
``Fine. These people are from your corner, not mine.''
The room fell silent. Jonny said nothing more about the fluctuations between strong cryptography and strong cryptanalysis. Agnes had made it clear that she didn't want to hear it. I found it interesting that those comments came from an FBI agent. It is the very agency for which Jonny works that seems to be unaware of these fluctuations. The FBI argument for key escrow hinges upon the belief that the latest swing in these fluctuations is an unprecedented event; past fluctuations are ignored.
As I sat there in the awkward silence, I mused over the key escrow debate. Key escrow is a procedure whereby part or all of a key is made available to a third party so that it can be recovered without the direct consent of the owner. The FBI would like to be able to use search warrants to access cryptographic keys used by private citizens. The FBI would like all domestic users of cryptography to place their keys in escrow. With the US government acting as the escrow agent, the FBI can gain access to these keys when the courts deem it appropriate.
Not long ago, the director of the FBI, Frank S. Samuelson, had gone before Congress to argue in favor of key escrow. A colleague had sent me a transcript of the opening remarks prepared by Samuelson. Among other things, he had said:
In a very fundamental way, conventional encryption has the effect of upsetting the delicate legal balance of the Fourth Amendment, since when a judge issues a search warrant it will be of no practical value when this type of encryption is encountered. Constitutionally-effective search and seizure law assumes, and the American public fully expects, that with warrant in hand law enforcement officers will be able to quickly act upon seized materials to solve and prevent crimes, and that prosecutors will be able to put understandable evidence before a jury. Conventional encryption virtually destroys this centuries old legal principle.
The references to a centuries old legal principle and to the upsetting of a delicate legal balance irked me most when I read this. What Samuelson fails to note anywhere in his speech is that the delicate balance to which he refers is so very delicate that it has swayed back and forth numerous times throughout the history of civilization. The latest swing is but the most recent fluctuation of many. There is no more reason to be alarmed with the current change than with any other shift.
Yes, as Samuelson says, the law and the public expect law enforcement to present any evidence that is obtainable (after getting a search warrant). I agree. Unfortunately for the Jonny, Agnes, and their associates, the content of recorded communications may no longer be obtained as easily as it once was. So be it; if the information is not obtainable, then neither the law nor the public expects law enforcement to be able to present it as evidence.
Surely nobody, including Samuelson, thinks that law enforcement should present as evidence the private musings of a suspected criminal. Such information is unobtainable, as everybody is well aware. Nobody expects the FBI to be mind readers. The FBI is expected only to present obtainable information.
If the FBI seizes my sneakers, they would be expected to attempt to learn as much as possible about them --- e.g. the manufacturer --- but if they are unable to determine where I was walking a year ago, even after careful examination of my sneakers by forensics experts, then does this mean that we must feel obligated to impose social constraints that make such information apparent from my sneakers? The suggestion seems ludicrous. Yet the only difference between the sneaker example and key escrow is that sneakers are common-place and well-understood. Cryptography is still new and unfamiliar to most people.
Nobody at the FBI complained when advances in technology opened up entirely new sources of evidence. Wire-tapping and electronic listening devices (bugs) are but two modern examples of technology that lend more power, not less, to a search warrant. It is now commonplace for whispered conversations, well out of ear-shot of the closest human being, to be obtainable by law enforcement. If Samuelson is going to appeal to the ``centuries old legal principle'' of search and seizure, then he must concede that the ``delicate balance'' has long since been destroyed. Encryption does not ``virtually destroy'' a centuries old legal principle, it merely sets it back closer to where it was a scant forty years ago, to a time when electronic surveillance was not practical.
I say let the FBI use wire-taps to collect any information they can (when they have a search warrant). There is no need to be alarmist about this. Should we ban water sprinklers and stereos? After all, people often use both of these devices to drown out personal conversations when they suspect they are being bugged. Do stereos represent a threat to American public safety? Of course not. To put the whole key escrow debate in context, one should keep two thoughts in mind:
Methinks Samuelson exaggerates the threat to national security and public safety. More likely he is fiercely guarding an advantage attained about forty years ago by law enforcement --- an advantage he should have realized was undoubtedly only a temporary fluctuation in the periodic ebbing and flooding of the tide that is the game of cops and robbers.
Granted, when the beneficial uses of a new technology have been limited, and the detrimental uses apparent, our society has a history of restricting use. Guns must be registered, for example. Some narcotics are banned. But cryptography is different in that the primary use is beneficial --- protecting the privacy and integrity of remote communications. Banning or otherwise restricting cryptography is closer to banning automobiles than it is to banning firearms. Jonny's analogy was a good one, but I would take it a step further and draw a parallel between key escrow and a requirement that all cars have built-in rev-limiters to slow them down to less than 50 mph... except for police cars which would be capable of 80 mph so that law enforcement officers can chase and catch suspected criminals. This speed advantage would enable police to ``quickly act upon obtained information to solve a case,'' as Samuelson claims the American public demands.
Or, to stretch the analogy nearly to the breaking point, because key escrow lets the public use long keys but gives part of the keys to the FBI, it is analogous to cars that are manufactured with remote-control rev-limiters such that the police can push a button while sitting in a patrol car and slow down a getaway car. This would have foiled Bonnie and Clyde in their speedy Ford.
Proponents of key escrow argue that honest citizens should not mind such things. If the police are the only ones with the remote control units for rev-limiters, then it is still possible for one citizen to speed away from another. And, if police must have a search warrant before pushing the button, and if we trust the US government, then what is there to worry about?
Hmmm... Watergate... Federal taps on Martin Luther King... Hoover... Tokyo Rose... Iran-Contra... Do I trust the United States government? Only to a degree. I prefer to think of search warrants as a necessary protection against government intrusion, a protection that is necessary only because the ability of government to intrude is too great, not too weak.
Consider this: a natural progression from key escrow is full information escrow. Why not archive all human interaction (neverminding the impracticalities for the time being)? I could wear a microphone around my neck; all of my conversations could be encrypted with an escrowed key and recorded for later access with a search warrant. Now, when the FBI gets a warrant they can obtain not only any information they can gather from my house, but all of the escrowed voice recordings. Even whispered face-to-face conversations in a secluded outdoor setting would not be beyond the reach of a search warrant. Ludicrous? Orwellian? I agree. I will not voluntarily escrow private one-on-one face-to-face conversations. Nor will I voluntarily escrow private one-on-one remote message exchanges. I fail to see any great distinction between the two situations other than the small difference that the FBI has become accustomed to eavesdropping on electronic communications without any cooperation, whereas eavesdropping on a face-to-face rendez-vous is harder in today's world. I take the same stand on both: no microphone around my neck; no key escrow. No Big Brother.
Such a stand is not so terrible for society. Civilization existed prior to electronic surveillance. It is not as if the world suddenly became a safer and more comfortable place to live once wire-tapping became technically feasible. Furthermore, even when strong encryption is permitted, the FBI can still tap unencrypted communications. Not everybody will use strong encryption for everything --- its too expensive, too slow, and too awkward. Even when people do use cryptography, the same information is often available in other (unencrypted) forms (e.g. papers, books, disk files, and other forms of physical evidence). There is no shortage of forensics methods. The FBI has cited cases where ``unbreakable'' cryptography was used in crimes. Yet the crimes cited were solved. How? By more traditional forensic techniques.
Cryptography can even help, by making it harder for users of the Internet to hide. The next version of the Internet Protocol, IPv6, will include provisions for strong authentication. Technologies such as public-key cryptography give us the equivalent to unforgeable digital signatures and digital fingerprints. For that matter ---
The buzzer sounded on Agnes' desk, rudely interrupting my silent rebuttal to Samuelson's stance on cryptography. We all were startled by the buzzer. For a moment all four of us just stared at it. Nobody moved. The buzzer sounded a second time and now Agnes reached out and acknowledged it.
``Mr. Templemeyer is here Mrs. Brown,'' said the voice on the other end of the line. ``He has two gentlemen with him: Walt Little and Lorenzo Thomas.''
``Show them in.''
Then, to the three of us she said, ``It's showtime.''
As it turns out, `Little' was not only Walt's last name but also an apt description of his stature. As he and his associate walked into the room one could not help but note the contrast. Walt Little was probably about five feet tall and thin. He couldn't have weighed more than 120 pounds. I'd place him at about fifty-five years old, but his hair was still dark brown (and didn't appear to be dyed). A neatly trimmed beard and mustache adorned his face. Despite this, or perhaps because of it, his face had a sharply chiseled look.
Lorenzo Thomas, on the other hand, was much bigger, weighing about 175 pounds, none of which was flab. He had an imposing physique for somebody of his years. Mr. Thomas had short white hair which was beginning to thin a bit at the top. He too appeared to be in his late-fifties.
Templemeyer I already knew from our earlier meeting. Once again he was wearing a light grey suit with a white shirt. His tie was Burgundy with brown paisley.
Little and Agnes exchanged handshakes and pleasantries. Agnes showed none of the irritation over their punctuality that she had voiced earlier.
Jonny, Lisa, and I stood by waiting for our turn to be introduced. Mr. Thomas did the same.
``I'm pleased to have the assistance of the NSA on this matter,'' Agnes was saying. ``The FBI has been able to unravel much of the case and to uncover some of the lower-level culprits, but we have run into a bit of an impasse recently. I'm hoping that the NSA can help us move forward.''
``We received your memo earlier in the week,'' said Mr. Little. ``And of course Mr. Templemeyer has discussed the matter with us as well. The work of the FBI up to this stage has been quite impressive. No doubt you have pursued all available leads; I'm not sure if there is much we have to offer, but if we can be of any assistance at all...''
Nobody was willing to take the lead. Before Little and his companions had arrived Agnes had claimed that the NSA called the meeting. Now Little was implying that somebody at the FBI called the meeting, as I had suspected.
``Please have a seat,'' Agnes said as she gestured to the row of chairs lined up in front of her desk.
Little remained standing. ``This is Lorenzo Thomas,'' he said. ``He is our leading expert on DES. Based upon the content of your memo, I thought we might want his consultation in this meeting.'' Little had to look up to the man beside him as he said this. ``Lorenzo is a leader in the field. He has a PhD from MIT, was instrumental in the original work on DES, and more recently has contributed to Clipper and Skipjack. Don't hold that last part against him!'' Little looked in Lisa's direction as he said this, apparently having already guessed that she was not FBI. Lisa responded with a polite smile but said nothing. Agnes was not as amused. She motioned in Jonny's direction.
``This is James Carter. He is a case officer with the FBI. He specializes in cases of electronic crime. And, of course, the FBI in general is quite experienced in cases of banking crimes,'' she reminded Little.
Jonny nodded to both Little and Dr. Thomas and said, ``Please call me Jonny.''
Next was my turn. Agnes gestured toward me and said, ``Carl Raymond has been kind enough to join us today. He is in part responsible for this mess. You see Carl took it upon himself to explore the EFT network. In so doing he facilitated the crimes we are investigating. His methods are illegal, but he has been cooperating with us recently.''
OK, this wasn't the kindest of introductions, but I have to concede that it is accurate. I wasn't quite sure what to say. Should I apologize after an introduction like that? Before I could say anything Agnes continued with her introductions.
``This is Lisa Cryer. She is an ordinary bank customer that was victimized by Mr. Raymond's actions.''
Lisa was not as taken aback as I was by Agnes' cool remarks.
``Hello Mr. Little, Dr. Thomas,'' she said sweetly, extending her hand toward Mr. Little. As she shook hands with the two of them she said, ``I think you will find that Carl has been quite instrumental in the investigation.''
``Tell me about it,'' Little asked her pleasantly. He settled down into the seat Agnes had indicated earlier. Dr. Thomas and Mr. Templemeyer did the same. I stepped back a couple of steps and leaned against the window sill. As I sat listening to Lisa's explanation I tried to read Agnes' expression. She had introduced Lisa as an innocent bystander and yet it was Lisa that Little had turned to for a briefing. Agnes is a woman that is not accustomed to anything less than full control. Outwardly she remained neutral. She sat with her elbows on the arms of her chair and her hands pressed together in a steeple point under her nose as she listened to Lisa's explanation.
``What can we do to help?'' Little asked after Lisa had finished her lengthy narrative. ``All of you have done impressive work. All that seems to remain to be done is identify the culprit --- the `millwright' as you folks refer to him.
``I brought Lorenzo with me because of his knowledge of DES and MAC's, but now I am wondering if the NSA can help in a different capacity.
``My initial guess is that we are dealing with a protocol attack here and not a cryptanalytic attack on the MAC's themselves. It certainly would not surprise me. Cryptographic failures are usually at the protocol level and not in the underlying algorithms. In fact, we at the NSA joke that all the fuss over export restrictions is a moot point because it does not matter how strong the encryption algorithms are that people are exporting if they are using those algorithms in weak protocols. Of course, the NSA is the main proponent of export restrictions so we are laughing at ourselves when we say this.
``I will have our top protocol analysts take another look at the cryptographic protocols used for funds transfer.'' Little let out a short sigh and admitted that the NSA was part of the development process for all of the cryptographic standards for banking. If there were any flaws in those standards then they would be flaws that the NSA overlooked the first time around. He was hopeful, however, that with actual data and attack symptoms to study, the NSA analysts might find something they had overlooked the first time.
``Is there anything else we can do to help?'' Little asked Agnes. At this point I stood up from the window sill. I had been hoping to be able to bring the computing power of the NSA to bear on the problem. The NSA is rumored to have an awesome amount of computer power. Supposedly the NSA has more MIPS at their disposal than IBM, DEC, HP, and Hitachi combined. Nobody knows for sure. Everything about the NSA is classified; even the budget is classified because knowledge of the NSA budget would allow people to estimate the computer resources the NSA can bring to bear on code-cracking problems.
Even if the rumors are exaggerated, even a small fraction of the NSA resources would speed up our automated search. I was sure that this was what Little was offering. Unfortunately, before I could make the request, Agnes responded. She apparently had interpreted Little's comments differently.
``Thank you, Walt. You are correct in describing our situation as one of knowing how the crime was committed but not yet knowing the identity of the perpetrator. Nor do we know his motive, although financial gain seems the obvious reason.
``As I'm sure you will agree, the Bureau has considerable experience with criminal profiles. We are confident that we can build an accurate profile for this case. In fact, Jonny can report on some of our progress. Jonny?''
Jonny stood up and walked over to an easel that had been set up near the window. I would have to wait for a better chance to ask Little for CPU help. I stepped away to give Jonny more room and walked over toward Lisa. When our eyes met Lisa rolled her eyes slightly and twitched her lips in a subtle smile. I briefly acknowledged her reaction with a similar one of my own, hoping that Agnes didn't notice. I did not need to worry; Agnes was attentively watching Jonny's presentation. He was flipping through the pages on the easel, having already finished with the first page. The second page listed several traits the FBI believed described the millwright:
I wasn't sure how they had arrived at some of these characteristics. The list had grown since the last time I'd seen it. I noticed that they still hadn't narrowed the age range much. At least they were ruling out the stereo-typical 16-year-old hackers that seem to be blamed for everything ever since the movie War Games came out.
Lisa had chuckled softly when Jonny mentioned that the suspect was known to be a ``computer geek.'' And she showed her skepticism (or was it irritation over perceived sexism?) when he said the suspect was ``known to be male.''
After completing the millwright profile, Jonny went on to explain that the FBI was reluctant to alert all banks of the trouble. The FBI feared that doing so would have the affect of also alerting the millwright. If the millwright were to shut down the mill and go into hiding, then he might never be caught. Given the scope of the crime, the FBI desperately wanted to catch the man behind the mill. Agnes hastened to explain that she had gotten clearance from the highest levels of the Justice Department to allow the mill to continue to operate in the hopes that the continued operation would expose new clues. As a result, First Chicago Trust and Bendix of St. Louis were the only two banks in the world that were aware of any peculiar activity in the EFT networks.
Of course the issue of allowing the mill to continue was a moot point since nobody had the foggiest idea how to shut it down. How do you stop someone from cracking DES? DES is supposed to be uncrackable. It is an integral part of the EFT system.
The two NSA men and Templemeyer listened to Jonny's carefully scripted presentation without interruption. When he was finished Little said, ``yes, well it looks like you have the criminal investigation under control. As you said Agnes, the FBI is in their element there and while the NSA would be happy to help, I doubt that there is much we can do for you there.
``On the other hand, perhaps more can be done on the technical side...''
I wasn't going to let this opportunity slip by a second time. I said, ``One area where we can use some immediate help is CPU cycles.''
Little turned in my direction. ``We can certainly let you have some cycles. Just give us your source code,'' Little replied. He seemed relieved to be discussing the technical issues again.
``What does your program do?'' Dr. Thomas asked.
``We have two programs,'' Lisa answered. ``The first is a more-or-less futile attempt to trace the bogus EFT's through the full graph. The program simply tests paths haphazardly. We recognize, of course, that there is an exponential number of paths, but we're desperate enough to try anything. Who knows, maybe we can stumble upon one of the millwright's bank accounts.'' She paused briefly and smiled sheepishly toward Dr. Thomas. I doubt that his response helped ease her embarrassment.
``Yeah, I'd say that's a long shot. What's the other program?''
Anxious to re-establish her credibility, Lisa told him about BIF. ``The other program uses a statistical approach to try to identify suspect bank accounts. We analyze each bank account in isolation. We are hoping to be able to sift through all of the accounts in the system for suspicious accounts and then analyze those by hand. We are looking for any accounts with unusual activity. Of course writing programs to automate the search requires that we define what we mean by `unusual'.
``We've designed and implemented a small rule-based language that allows us to write simple rules to characterize unusual account activity. This makes it possible to change the rules easily and thereby redefine the profiles for suspicious accounts.''
I picked up the explanation at this point. ``We have several rule sets that we have developed already,'' I explained, ``and we have been experimenting with them. The trouble is that the program is extremely slow. Testing a single bank account is order n2 where n is the number of rules. On top of that, some of the individual rules take a long time to run against a single account. When you consider that there are millions of bank accounts in the EFT network you can appreciate just how big the problem is. Even for our current rule sets, which are still much smaller than the profiles we anticipate we'll want to use soon, it takes us about a week to run through all the data we have.''
``What are you running it on now?''
Lisa answered. ``We are using a couple of Pentiums running Linux. I think they are 150 MHz and 90 MHz,'' she said, as she glanced toward me for confirmation. I nodded and added that the code was written in C. Dr. Thomas nodded his head, apparently satisfied with this answer.
``That should be easy to port,'' he said. ``Would you be upset if we tinkered with the source a bit? We have some people that are quite skilled at optimizing programs for performance. In fact, it sounds like this problem may lend itself quite nicely to a parallel algorithm.''
``Absolutely!'' exclaimed Lisa. ``This is an excellent opportunity for parallelism. Not only do we test each bank account independently, but even within the tests for a single account there are opportunities for parallel testing of rules.''
``How soon can you get the source to us?'' asked Little.
``We can give you a tape before you leave here today,'' Lisa replied.
Both Mr. Little and Dr. Thomas seemed pleased with this and Mr. Little stood up as if to go. Agnes still had some matters she apparently wanted to discuss, but seemed reluctant to do so with the rest of us in the room. Sensing this, I suggested that Lisa and I go prepare the tape. Jonny said he'd join us, and the three of us left. As we closed the door behind us I heard Agnes saying once again that the Bureau was pleased to have the assistance of the NSA but that the criminal investigation was well under control and that they really didn't need help.
``Turf wars,'' muttered Jonny. I wasn't sure whether I should feel sorry for Agnes or disgusted. I decided to feel sorry; I liked Agnes.