NEW YORK (

TheStreet

) --

Cisco

(CSCO) - Get Report

released earnings last week and lowered its revenue guidance for next quarter as well as for its fiscal year 2011 based on a slowdown in public spending. Cisco competes with

Juniper

(JNPR) - Get Report

,

Alcatel-Lucent

(ALU)

and

Tellabs

(TLAB)

in the routing and switching businesses.

We currently forecast that Cisco will maintain its dominant market share in excess of 70% for the routing and switching businesses, but if it loses 5% share in each of these businesses due to its higher exposure to the public sector, this would translate to around 4%-5% downside to our lowered price estimate.

As a result of the company's weaker guidance, we have lowered our price estimate for Cisco's stock to $24.04, which is about 20% above the current market price.

Weak Public Sector Spending

Unlike its enterprise business, the public sector business has slowed considerably for Cisco. The company stated that for Q1 2011 fiscal year, public sector order growth was a modest 6% versus enterprise order growth of 16%, on a year-over-year basis.

Most of this slowdown was caused by significant reductions in public spending. Facing budget deficits, the U.S., Japan and some Central European countries reigned in its IT spending more than expected. Cisco stated that it will continue to face these challenges over the next few quarters, and we believe this holds negative implications for its market share outlook.

Market Share Outlook

As Cisco's products tend to be more expensive compared to its competitors, public budget constraints will continue to hurt Cisco's order growth in the coming quarters as officials look for cheaper alternatives.

We estimate that about 20% of Cisco's product revenues come from the public sector. According to industry analysts, Cisco has higher exposure to the government sector compared to its competitors. Therefore its higher relative dependence on public spending could result in combined market share losses if other segments continue to outpace public spending.

Currently we forecast a largely stable market share for Cisco's routers and switches units. However, if its market share declines by 5% in both segments versus our expectations, our price estimate could see additional downside of 4% to 5%.

In these charts, you can see how changes in market share forecasts impact our price estimates.

You can see the

complete $24.04 Trefis price estimate for Cisco's stock here.

Like our charts? Embed them in your own posts using the

Trefis Wordpress Plugin

.

Trefis

is a financial community structured around trends, forecasts and insights related to some of the most popular stocks in the U.S.