The NASDAQ OMX Group, Inc. (NASDAQ:NDAQ) options market has resumed trading after a technical problem caused a halt earlier today. The exchange revealed that a problem in a data feed necessitated the halting of all trading on the options markets. That news came at 12:14 pm Eastern time today. The return of trading to the index will be a relief to traders, but it raises longer term questions about the Nasdaq and computerized stock exchanges in general.

Nasdaq omx

Nasdaq technical problems

Technical problems on today’s market raised new questions about the ability of market infrastructure in the United States to consistently offer a high level of effectiveness. News of the NASDAQ OMX Group, Inc. (NASDAQ:NDAQ) halt came just days after the NYSE Euronext (NYSE:NYX) revealed a number of false trades hit their options market on Tuesday.

The increasing prevalence of glitches in the stock exchanges is accompanied by increasing automation in both exchanges and the trading houses sending orders. Tuesday’s problem resulted from an error at Goldman Sachs Group, Inc. (NYSE:GS). Today’s problem originated inside the Nasdaq exchange itself.

In May of last year, the NASDAQ OMX Group, Inc. (NASDAQ:NDAQ was hit with a wave of criticism after its systems failed to deal with the Facebook Inc (NASDAQ:FB) IPO effectively. The fallout from that issue led to lawsuits and eventually large settlements which had to be paid by the exchange. As technical problems continue to hit the market, it is likely that regulators and oversight groups will take a more active approach in dealing with market infrastructure.

Nasdaq halt over

NASDAQ OMX Group, Inc. (NASDAQ:NDAQ) said in a statement earlier today that the halt in trading would not result in the cancellation of open orders, but said that customers could decide to cancel their own orders because of faults in the system. During the freeze the NYSE Euronext (NYSE:NYX) also halted trading in all Nasdaq listed securities at the request of that exchange.

The restart in trading on the index will be accompanied by a sigh of relief from investors, but oversight and systems personnel at the exchange are likely only getting started with their work. A stock exchange halt is a serious issue, and regulators will be interested in the reasons for today’s freeze.