<SUBMISSION>
<ACCESSION-NUMBER>0000950133-08-002411
<TYPE>8-K
<PUBLIC-DOCUMENT-COUNT>2
<PERIOD>20080716
<ITEMS>2.06
<ITEMS>9.01
<FILING-DATE>20080718
<DATE-OF-FILING-DATE-CHANGE>20080718
<FILER>
<COMPANY-DATA>
<CONFORMED-NAME>CIENA CORP
<CIK>0000936395
<ASSIGNED-SIC>3661
<IRS-NUMBER>232725311
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1031
</COMPANY-DATA>
<FILING-VALUES>
<FORM-TYPE>8-K
<ACT>34
<FILE-NUMBER>000-21969
<FILM-NUMBER>08958738
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>1201 WINTERSON ROAD
<CITY>LINTHICUM
<STATE>MD
<ZIP>21090
<PHONE>4108658500
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>1201 WINTERSON ROAD
<CITY>LINTHICUM
<STATE>MD
<ZIP>21090
</MAIL-ADDRESS>
</FILER>
<DOCUMENT>
<TYPE>8-K
<SEQUENCE>1
<FILENAME>w63463e8vk.htm
<DESCRIPTION>FORM 8-K
<TEXT>
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<TITLE>e8vk</TITLE>
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<DIV style="width: 100%; border-bottom: 2pt solid black; font-size: 1pt">&nbsp;</DIV>
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<DIV align="center" style="font-size: 14pt; margin-top: 12pt"><B>UNITED STATES<BR>
SECURITIES AND EXCHANGE COMMISSION</B>
</DIV>

<DIV align="center" style="font-size: 12pt"><B>WASHINGTON, DC 20549</B>
</DIV>

<DIV align="center" style="font-size: 18pt; margin-top: 12pt"><B>FORM 8-K</B>
</DIV>


<DIV align="center" style="font-size: 12pt; margin-top: 12pt"><B>CURRENT REPORT PURSUANT<BR>
TO SECTION 13 OR 15(D) OF THE<BR>
SECURITIES EXCHANGE ACT OF 1934</B>
</DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 12pt"><B>Date of report (Date of earliest event reported) </B><U><B>July&nbsp;16, 2008</B></U></DIV>

<DIV align="center" style="font-size: 24pt; margin-top: 12pt"><B> Ciena Corporation</B>
</DIV>
<DIV align="center">
<DIV style="font-size: 1pt; margin-top: 0pt; width: 40%; border-top: 1px solid #000000">&nbsp;</DIV></DIV>
<DIV align="center" style="font-size: 10pt">(Exact Name of Registrant as Specified in Its Charter)</DIV>


<DIV align="center" style="font-size: 10pt; margin-top: 12pt"><B>Delaware</B></DIV>

<DIV align="center" style="font-size: 10pt"><DIV style="width: 100%; border-bottom: 1px solid #000000; font-size: 1px">&nbsp;</DIV>
(State or Other Jurisdiction of Incorporation)</DIV>


<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="47%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="47%">&nbsp;</TD>
</TR>
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<TR valign="bottom">
    <TD align="center" valign="top"><B>0-21969</B>
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top"><B>23-2725311</B></TD>
</TR>
<TR style="font-size: 1px">
    <TD colspan="3" valign="top" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD align="center" valign="top">(Commission File Number)
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">(IRS Employer Identification No.)</TD>
</TR>
<!-- End Table Body -->
</TABLE>
</DIV>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="47%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="47%">&nbsp;</TD>
</TR>
<!-- End Table Head -->
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<TR valign="bottom">
    <TD align="center" valign="top"><B>1201 Winterson Road, Linthicum, MD</B>
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top"><B>21090</B></TD>
</TR>
<TR style="font-size: 1px">
    <TD colspan="3" valign="top" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD align="center" valign="top">(Address of Principal Executive Offices)
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">(Zip Code)</TD>
</TR>
<!-- End Table Body -->
</TABLE>
</DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 12pt"><B>(410)&nbsp;865-8500</B></DIV>

<DIV align="center" style="font-size: 10pt"><DIV style="width: 100%; border-bottom: 1px solid #000000; font-size: 1px">&nbsp;</DIV></DIV>


<DIV align="center" style="font-size: 10pt">(Registrant&#146;s Telephone Number, Including Area Code)</DIV>


<DIV align="center" style="font-size: 10pt; margin-top: 12pt"><DIV style="width: 100%; border-bottom: 1px solid #000000; font-size: 1px">&nbsp;</DIV></DIV>

<DIV align="center" style="font-size: 10pt">(Former Name or Former Address, if Changed Since Last Report)</DIV>



<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy
the filing obligation of the registrant under any of the following provisions (<I>see </I>General
Instruction A.2. below):
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<FONT face="Wingdings">&#111;</FONT> Written communications pursuant to Rule&nbsp;425 under the Securities Act (17 CFR 230.425)
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<FONT face="Wingdings">&#111;</FONT> Soliciting material pursuant to Rule&nbsp;14a-12 under the Exchange Act (17 CFR 240.14a-12)
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<FONT face="Wingdings">&#111;</FONT> Pre-commencement communications pursuant to Rule&nbsp;14d-2(b) under the Exchange Act (17
CFR 240.14d-2(b))
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<FONT face="Wingdings">&#111;</FONT> Pre-commencement communications pursuant to Rule&nbsp;13e-4(c) under the Exchange Act (17
CFR 240.13e-4(c))
</DIV>

<DIV style="width: 100%; border-bottom: 1pt solid black; margin-top: 10pt; font-size: 1pt">&nbsp;</DIV>
<DIV style="width: 100%; border-bottom: 2pt solid black; font-size: 1pt">&nbsp;</DIV>





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<!-- link1 "ITEM 2.06 &#151; MATERIAL IMPAIRMENTS" -->

<DIV align="left" style="font-size: 10pt; margin-top: 12pt"><B>ITEM 2.06 &#150; MATERIAL IMPAIRMENTS</B>
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;On July&nbsp;18, 2008, Ciena Corporation issued a press release relating to the impairment of its
investments in commercial paper issued by two structured investment vehicles. On July&nbsp;16, 2008,
Ciena received updated valuation information from its investment manager associated with an auction
process for the assets of one of these structured investment vehicles, and Ciena concluded that an
other-than-temporary impairment of these investments had occurred. The information contained in the
press release attached as Exhibit&nbsp;99.1 to this Current Report on Form 8-K is incorporated by
reference into this Item&nbsp;2.06.
</DIV>

<!-- link1 "ITEM 9.01 &#151; FINANCIAL STATEMENTS AND EXHIBITS" -->

<DIV align="left" style="font-size: 10pt; margin-top: 6pt"><B>ITEM 9.01 &#150; FINANCIAL STATEMENTS AND EXHIBITS</B>
&nbsp;
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;The following exhibit is being filed herewith:<BR>
&nbsp;
</DIV>
<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
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    <TD width="8%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="90%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD nowrap align="left" style="border-bottom: 1px solid #000000">Exhibit Number</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="left" style="border-bottom: 1px solid #000000">Description of Document</TD>
</TR>

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    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">Exhibit&nbsp;99.1
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Text of press release dated July&nbsp;18, 2008, issued by Ciena Corporation.</TD>
</TR>
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<DIV align="center" style="font-size: 10pt; margin-top: 18pt"><B>SIGNATURES</B>
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused
this report to be signed on its behalf by the undersigned thereunto duly authorized.
</DIV>


<TABLE width="100%" border="0" cellspacing="0" cellpadding="0" style="font-size: 10pt">
<TR>
    <TD width="48%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="35%">&nbsp;</TD>
    <TD width="15%">&nbsp;</TD>
</TR>
<TR>
    <TD valign="top" align="left">&nbsp;</TD>
    <TD colspan="3" align="left"><B>Ciena Corporation</B><BR>
&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR><TR>
    <TD align="left">Date: July 18, 2008&nbsp;</TD>
    <TD valign="top">By:&nbsp;&nbsp;</TD>
    <TD colspan="2" style="border-bottom: 1px solid #000000" align="left">/S/ Russell B. Stevenson, Jr.
&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR><TR>
    <TD align="left">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="2" align="left">Russell B. Stevenson, Jr.&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR><TR>
    <TD align="left">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="2" align="left">Senior Vice President, General Counsel and
Secretary&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>
</TABLE>


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<TYPE>EX-99.1
<SEQUENCE>2
<FILENAME>w63463exv99w1.htm
<DESCRIPTION>EX-99.1
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<TITLE>exv99w1</TITLE>
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<DIV align="right" style="font-size: 10pt; margin-top: 12pt"><B>EXHIBIT 99.1</B>
</DIV>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="60%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="15%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="15%">&nbsp;</TD>
</TR>
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<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><B>Press Contact</B>:
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Nicole Anderson<br>
Ciena Corporation<br>
(410)&nbsp;694&#150;5786<br>
<u>pr@ciena.com</u></TD>
</TR>

<TR>
<TD style="font-size: 10pt">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><B>Investor Contact</B>:
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Marie Downing<br>
Ciena Corporation<br>
(888)&nbsp;243-6223<br>
<u>ir@ciena.com</u></TD>
</TR>
<!-- End Table Body -->
</TABLE>
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 12pt"><U><B>FOR IMMEDIATE RELEASE</B></U>
</DIV>


<DIV align="center" style="font-size: 10pt; margin-top: 18pt"><B>Ciena expects $5.0 to $6.0&nbsp;million Q3 GAAP loss related to commercial paper<BR>
investments</B>
</DIV>


<DIV align="Center" style="font-size: 10pt; margin-top: 6pt"><I>GAAP loss will not affect Ciena&#146;s income from operations</I>

</DIV>
<DIV align="left" style="font-size: 10pt; margin-top: 6pt"><B>LINTHICUM, Md. &#150; July&nbsp;18, 2008 &#150; </B>Ciena<SUP style="font-size: 85%; vertical-align: text-top">&#174;</SUP> Corporation (NASDAQ: CIEN) today announced that
it expects to recognize a GAAP loss totaling between $5.0&nbsp;million and $6.0&nbsp;million in the third
quarter of fiscal 2008, relating to commercial paper investments in Rhinebridge LLC and SIV
Portfolio plc (formerly known as Cheyne Finance plc). Ciena had previously recognized a loss of
$13.0&nbsp;million related to its investment in these two structured investment vehicles (SIVs), each of
which entered into receivership and failed to make payment at maturity during the fourth quarter of
Ciena&#146;s fiscal 2007.
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">At April&nbsp;30, 2008, Ciena&#146;s commercial paper issued by these SIVs had a carrying value of $25.6
million. The estimated GAAP loss for the third quarter is based upon valuation information provided
by Ciena&#146;s investment manager on July&nbsp;16, 2008 in connection with the restructuring of these SIVs.
This estimated GAAP loss will not affect Ciena&#146;s income from operations for the third quarter of
fiscal 2008. As stated previously, Ciena believes that its SIV-related exposure is limited to these
two investments.
</DIV>


<DIV align="center" style="font-size: 10pt; margin-top: 18pt"># # #
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 12pt"><B>About Ciena</B>
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">Ciena specializes&nbsp;in network&nbsp;transition. We&nbsp;provide the&nbsp;flexible platforms, intelligent software
and professional services&nbsp;to build&nbsp;converged networks&nbsp;for&nbsp;enhanced services and applications. With
a growing global presence,&nbsp;Ciena leverages&nbsp;its&nbsp;heritage&nbsp;of practical innovation&nbsp;to deliver&nbsp;maximum
performance and economic value in communications networks worldwide. For more information, visit
<u>www.ciena.com</u>.
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 12pt"><B>Note to Ciena Investors</B>
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">This press release contains certain forward-looking statements based on current expectations,
forecasts and assumptions that involve risks and uncertainties. These statements are based on
information available to the Company as of the date hereof; and Ciena&#146;s actual results could differ
materially from those stated or implied, due to
</DIV>
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<DIV align="left" style="font-size: 10pt; margin-top: 6pt">risks and uncertainties associated with its business, which include the risk factors disclosed in
its Report on Form 10-Q filed with the Securities and Exchange Commission on June&nbsp;6, 2008.
Forward-looking statements include statements regarding Ciena&#146;s expectations, beliefs, intentions
or strategies regarding the future and can be identified by forward-looking words such as
&#147;anticipate,&#148; &#147;believe,&#148; &#147;could,&#148; &#147;estimate,&#148; &#147;expect,&#148; &#147;intend,&#148; &#147;may,&#148; &#147;should,&#148; &#147;will,&#148; and
&#147;would&#148; or similar words. Forward-looking statements in this release include the statements that
Ciena &#147;expects to recognize a GAAP loss totaling between $5.0&nbsp;million and $6.0&nbsp;million in the third
quarter of fiscal 2008,&#148; &#147;this estimated GAAP loss will not affect Ciena&#146;s income from operations
for the third quarter of fiscal 2008&#148; and &#147;Ciena believes that its SIV-related exposure is limited
to these two investments.&#148; Ciena assumes no obligation to update the information included in this
press release, whether as a result of new information, future events or otherwise.
</DIV>



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