diff --git a/.gitignore b/.gitignore
index c818180b1..9d99cb176 100644
--- a/.gitignore
+++ b/.gitignore
@@ -30,3 +30,6 @@ zcnbridge/example/logs/
 winsdk/zcn.windows.h
 wasmsdk/cypress/node_modules/
 wasmsdk/demo/demo
+sdkversion.go
+gosdk.code-workspace
+sdkversion
diff --git a/constants/context_key.go b/constants/context_key.go
index 30764cfee..b4c264035 100644
--- a/constants/context_key.go
+++ b/constants/context_key.go
@@ -16,5 +16,6 @@ const (
 	ContextKeyAllocationID ContextKey = "allocation_id"
 
 	// ContextKeyClientSignatureHeaderKey represents key for context value passed with common.ClientSignatureHeader request header.
-	ContextKeyClientSignatureHeaderKey ContextKey = "signature"
+	ContextKeyClientSignatureHeaderKey   ContextKey = "signature"
+	ContextKeyClientSignatureHeaderV2Key ContextKey = "signature_v2"
 )
diff --git a/wasmsdk/blobber.go b/wasmsdk/blobber.go
index fcbc14c93..866ff3449 100644
--- a/wasmsdk/blobber.go
+++ b/wasmsdk/blobber.go
@@ -839,11 +839,19 @@ func upload(allocationID, remotePath string, fileBytes, thumbnailBytes []byte, w
 }
 
 // download download file blocks
-func downloadBlocks(alloc *sdk.Allocation, remotePath, authTicket, lookupHash string, startBlock, endBlock int64) ([]byte, error) {
+func downloadBlocks(allocId string, remotePath, authTicket, lookupHash string, startBlock, endBlock int64) ([]byte, error) {
+
 	if len(remotePath) == 0 && len(authTicket) == 0 {
 		return nil, RequiredArg("remotePath/authTicket")
 	}
 
+	alloc, err := getAllocation(allocId)
+
+	if err != nil {
+		PrintError("Error fetching the allocation", err)
+		return nil, err
+	}
+
 	var (
 		wg        = &sync.WaitGroup{}
 		statusBar = &StatusBar{wg: wg}
diff --git a/wasmsdk/player_file.go b/wasmsdk/player_file.go
index 440f65b9c..ccafe75f2 100644
--- a/wasmsdk/player_file.go
+++ b/wasmsdk/player_file.go
@@ -66,7 +66,7 @@ func (p *FilePlayer) download(startBlock int64) {
 	}
 	fmt.Println("start:", startBlock, "end:", endBlock, "numBlocks:", p.numBlocks, "total:", p.playlistFile.NumBlocks)
 
-	data, err := downloadBlocks(p.allocationObj, p.remotePath, p.authTicket, p.lookupHash, startBlock, endBlock)
+	data, err := downloadBlocks(p.allocationObj.ID, p.remotePath, p.authTicket, p.lookupHash, startBlock, endBlock)
 	// data, err := downloadBlocks2(int(startBlock), int(endBlock), p.allocationObj, p.remotePath)
 	if err != nil {
 		PrintError(err.Error())
diff --git a/zboxcore/sdk/blockdownloadworker.go b/zboxcore/sdk/blockdownloadworker.go
index 9420375fd..b4e48f9ab 100644
--- a/zboxcore/sdk/blockdownloadworker.go
+++ b/zboxcore/sdk/blockdownloadworker.go
@@ -136,6 +136,7 @@ func (req *BlockDownloadRequest) downloadBlobberBlock() {
 		header.NumBlocks = req.numBlocks
 		header.VerifyDownload = req.shouldVerify
 		header.ConnectionID = req.connectionID
+		header.Version = "v2"
 
 		if req.authTicket != nil {
 			header.AuthToken, _ = json.Marshal(req.authTicket) //nolint: errcheck
diff --git a/zboxcore/sdk/download_reqeust_header.go b/zboxcore/sdk/download_reqeust_header.go
index 3606e4618..c447e0db9 100644
--- a/zboxcore/sdk/download_reqeust_header.go
+++ b/zboxcore/sdk/download_reqeust_header.go
@@ -18,6 +18,7 @@ type DownloadRequestHeader struct {
 	DownloadMode   string
 	VerifyDownload bool
 	ConnectionID   string
+	Version        string
 }
 
 // ToHeader update header
@@ -51,5 +52,9 @@ func (h *DownloadRequestHeader) ToHeader(req *http.Request) {
 		req.Header.Set("X-Connection-ID", h.ConnectionID)
 	}
 
+	if h.Version != "" {
+		req.Header.Set("X-Version", h.Version)
+	}
+
 	req.Header.Set("X-Verify-Download", fmt.Sprint(h.VerifyDownload))
 }
diff --git a/zboxcore/sdk/filerefsworker.go b/zboxcore/sdk/filerefsworker.go
index e0f40fb2c..4aabd0683 100644
--- a/zboxcore/sdk/filerefsworker.go
+++ b/zboxcore/sdk/filerefsworker.go
@@ -116,6 +116,7 @@ func (o *ObjectTreeRequest) getFileRefs(oTR *oTreeResponse, bUrl string) {
 	oReq, err := zboxutil.NewRefsRequest(
 		bUrl,
 		o.allocationID,
+		o.allocationTx,
 		o.remotefilepath,
 		o.pathHash,
 		o.authToken,
diff --git a/zboxcore/zboxutil/http.go b/zboxcore/zboxutil/http.go
index 73c0519e0..8b30c32d5 100644
--- a/zboxcore/zboxutil/http.go
+++ b/zboxcore/zboxutil/http.go
@@ -76,8 +76,9 @@ const (
 	REDEEM_ENDPOINT              = "/v1/connection/redeem/"
 
 	// CLIENT_SIGNATURE_HEADER represents http request header contains signature.
-	CLIENT_SIGNATURE_HEADER = "X-App-Client-Signature"
-	ALLOCATION_ID_HEADER    = "ALLOCATION-ID"
+	CLIENT_SIGNATURE_HEADER    = "X-App-Client-Signature"
+	CLIENT_SIGNATURE_HEADER_V2 = "X-App-Client-Signature-V2"
+	ALLOCATION_ID_HEADER       = "ALLOCATION-ID"
 )
 
 func getEnvAny(names ...string) string {
@@ -167,15 +168,22 @@ func setClientInfo(req *http.Request) {
 	req.Header.Set("X-App-Client-Key", client.GetClientPublicKey())
 }
 
-func setClientInfoWithSign(req *http.Request, allocation string) error {
+func setClientInfoWithSign(req *http.Request, allocation, baseURL string) error {
 	setClientInfo(req)
 
-	sign, err := client.Sign(encryption.Hash(allocation))
+	hashData := allocation
+	sign, err := client.Sign(encryption.Hash(hashData))
 	if err != nil {
 		return err
 	}
 	req.Header.Set(CLIENT_SIGNATURE_HEADER, sign)
 
+	hashData = allocation + baseURL
+	sign, err = client.Sign(encryption.Hash(hashData))
+	if err != nil {
+		return err
+	}
+	req.Header.Set(CLIENT_SIGNATURE_HEADER_V2, sign)
 	return nil
 }
 
@@ -216,7 +224,7 @@ func NewReferencePathRequest(baseUrl, allocationID string, allocationTx string,
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -262,7 +270,7 @@ func NewObjectTreeRequest(baseUrl, allocationID string, allocationTx string, pat
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -271,7 +279,7 @@ func NewObjectTreeRequest(baseUrl, allocationID string, allocationTx string, pat
 	return req, nil
 }
 
-func NewRefsRequest(baseUrl, allocationID, path, pathHash, authToken, offsetPath, updatedDate, offsetDate, fileType, refType string, level, pageLimit int) (*http.Request, error) {
+func NewRefsRequest(baseUrl, allocationID, allocationTx, path, pathHash, authToken, offsetPath, updatedDate, offsetDate, fileType, refType string, level, pageLimit int) (*http.Request, error) {
 	nUrl, err := joinUrl(baseUrl, REFS_ENDPOINT, allocationID)
 	if err != nil {
 		return nil, err
@@ -295,7 +303,7 @@ func NewRefsRequest(baseUrl, allocationID, path, pathHash, authToken, offsetPath
 
 	req.Header.Set(ALLOCATION_ID_HEADER, allocationID)
 
-	if err := setClientInfoWithSign(req, allocationID); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -321,7 +329,7 @@ func NewRecentlyAddedRefsRequest(bUrl, allocID, allocTx string, fromDate, offset
 
 	req.Header.Set(ALLOCATION_ID_HEADER, allocID)
 
-	if err = setClientInfoWithSign(req, allocID); err != nil {
+	if err := setClientInfoWithSign(req, allocTx, bUrl); err != nil {
 		return nil, err
 	}
 
@@ -356,7 +364,7 @@ func NewCollaboratorRequest(baseUrl string, allocationID string, allocationTx st
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -376,7 +384,7 @@ func GetCollaboratorsRequest(baseUrl string, allocationID string, allocationTx s
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -397,7 +405,7 @@ func DeleteCollaboratorRequest(baseUrl string, allocationID string, allocationTx
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -416,8 +424,7 @@ func NewFileMetaRequest(baseUrl string, allocationID string, allocationTx string
 		return nil, err
 	}
 
-	err = setClientInfoWithSign(req, allocationTx)
-	if err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -436,7 +443,7 @@ func NewFileStatsRequest(baseUrl string, allocationID string, allocationTx strin
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -487,7 +494,7 @@ func NewUploadRequestWithMethod(baseURL, allocationID string, allocationTx strin
 	}
 
 	// set header: X-App-Client-Signature
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseURL); err != nil {
 		return nil, err
 	}
 
@@ -513,8 +520,7 @@ func NewWriteMarkerLockRequest(
 		return nil, err
 	}
 
-	err = setClientInfoWithSign(req, allocationTx)
-	if err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseURL); err != nil {
 		return nil, err
 	}
 
@@ -536,8 +542,7 @@ func NewWriteMarkerUnLockRequest(
 		return nil, err
 	}
 
-	err = setClientInfoWithSign(req, allocationTx)
-	if err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseURL); err != nil {
 		return nil, err
 	}
 
@@ -562,7 +567,7 @@ func NewUploadRequest(baseUrl, allocationID string, allocationTx string, body io
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -581,7 +586,7 @@ func NewConnectionRequest(baseUrl, allocationID string, allocationTx string, bod
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -602,7 +607,7 @@ func NewRenameRequest(baseUrl, allocationID string, allocationTx string, body io
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -622,7 +627,7 @@ func NewCopyRequest(baseUrl, allocationID string, allocationTx string, body io.R
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -642,7 +647,7 @@ func NewMoveRequest(baseUrl, allocationID string, allocationTx string, body io.R
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -662,7 +667,9 @@ func NewDownloadRequest(baseUrl, allocationID, allocationTx string) (*http.Reque
 	if err != nil {
 		return nil, err
 	}
-	setClientInfo(req)
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
+		return nil, err
+	}
 
 	req.Header.Set(ALLOCATION_ID_HEADER, allocationID)
 
@@ -696,7 +703,7 @@ func NewDeleteRequest(baseUrl, allocationID string, allocationTx string, query *
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -716,7 +723,7 @@ func NewCreateDirRequest(baseUrl, allocationID string, allocationTx string, body
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -736,7 +743,7 @@ func NewShareRequest(baseUrl, allocationID string, allocationTx string, body io.
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -756,7 +763,7 @@ func NewRevokeShareRequest(baseUrl, allocationID string, allocationTx string, qu
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}
 
@@ -777,7 +784,7 @@ func NewWritemarkerRequest(baseUrl, allocationID, allocationTx string) (*http.Re
 		return nil, err
 	}
 
-	if err := setClientInfoWithSign(req, allocationTx); err != nil {
+	if err := setClientInfoWithSign(req, allocationTx, baseUrl); err != nil {
 		return nil, err
 	}